Wordpress-operator panics -> `panic: reflect: slice length out of range in SetLen`

[droslean]

panic: reflect: slice length out of range in SetLen

goroutine 372 [running]:
reflect.Value.SetLen({0x1309440, 0xc000069720, 0x143e4e0}, 0x15)
	/usr/local/go/src/reflect/value.go:2016 +0x8d
github.com/presslabs/controller-util/mergo/transformers.(*TransformerMap).MergeListByKey.func1({0x1309440, 0xc000069720, 0x1309440}, {0x1309440, 0xc0012b9950, 0x400})
	/workspace/src/github.com/bitpoke/wordpress-operator/.work/pkg/pkg/mod/github.com/presslabs/[email protected]/mergo/transformers/transformers.go:174 +0x385
github.com/imdario/mergo.deepMerge({0x1309440, 0xc000069720, 0x1501840}, {0x1309440, 0xc0012b9950, 0x2c}, 0x0, 0x1, 0xc00082d700)
	/workspace/src/github.com/bitpoke/wordpress-operator/.work/pkg/pkg/mod/github.com/imdario/[email protected]/merge.go:84 +0xf53
github.com/imdario/mergo.deepMerge({0x1501840, 0xc000069690, 0x1501840}, {0x1501840, 0xc0012b98c0, 0x2c}, 0xc0012c87d0, 0x0, 0xc00082d700)
	/workspace/src/github.com/bitpoke/wordpress-operator/.work/pkg/pkg/mod/github.com/imdario/[email protected]/merge.go:93 +0x1030
github.com/imdario/mergo.merge({0x14af8e0, 0xc000069690}, {0x1501840, 0xc0012b98c0}, {0xc00030d100, 0x2, 0xc000069690})
	/workspace/src/github.com/bitpoke/wordpress-operator/.work/pkg/pkg/mod/github.com/imdario/[email protected]/merge.go:366 +0x2ab
github.com/imdario/mergo.Merge(...)
	/workspace/src/github.com/bitpoke/wordpress-operator/.work/pkg/pkg/mod/github.com/imdario/[email protected]/merge.go:296
github.com/presslabs/controller-util/mergo/transformers.(*TransformerMap).mergeByKey(0x221c3b8, {0x153a766, 0x4}, {0x13091c0, 0xc00057e6b8, 0xc00082c940}, {0x1501840, 0xc0004fcd90, 0x0}, {0xc00000e198, ...})
	/workspace/src/github.com/bitpoke/wordpress-operator/.work/pkg/pkg/mod/github.com/presslabs/[email protected]/mergo/transformers/transformers.go:94 +0x2da
github.com/presslabs/controller-util/mergo/transformers.(*TransformerMap).MergeListByKey.func1({0x13091c0, 0xc00057e6b8, 0x13091c0}, {0x13091c0, 0xc00000a978, 0x11})
	/workspace/src/github.com/bitpoke/wordpress-operator/.work/pkg/pkg/mod/github.com/presslabs/[email protected]/mergo/transformers/transformers.go:163 +0x239
github.com/appscode/mergo.deepMerge({0x13091c0, 0xc00057e6b8, 0x1520ca0}, {0x13091c0, 0xc00000a978, 0xc0012c8f10}, 0xc0012c9048, 0x1, 0xc001484f60)
	/workspace/src/github.com/bitpoke/wordpress-operator/.work/pkg/pkg/mod/github.com/appscode/[email protected]/merge.go:63 +0xc5b
github.com/appscode/mergo.deepMerge({0x1520ca0, 0xc00057e6a0, 0x1520ca0}, {0x1520ca0, 0xc00000a960, 0x9}, 0xc00000a960, 0x0, 0xc001484f60)
	/workspace/src/github.com/bitpoke/wordpress-operator/.work/pkg/pkg/mod/github.com/appscode/[email protected]/merge.go:72 +0xd2a
github.com/appscode/mergo.merge({0x14b6c60, 0xc00057e6a0}, {0x1520ca0, 0xc00000a960}, {0xc0012c9388, 0x1, 0x0})
	/workspace/src/github.com/bitpoke/wordpress-operator/.work/pkg/pkg/mod/github.com/appscode/[email protected]/merge.go:251 +0x20b
github.com/appscode/mergo.Merge(...)
	/workspace/src/github.com/bitpoke/wordpress-operator/.work/pkg/pkg/mod/github.com/appscode/[email protected]/merge.go:206
github.com/bitpoke/wordpress-operator/pkg/controller/wordpress/internal/sync.NewDeploymentSyncer.func1()
	/workspace/src/github.com/bitpoke/wordpress-operator/pkg/controller/wordpress/internal/sync/deploy.go:71 +0x5c5
github.com/presslabs/controller-util/syncer.(*ObjectSyncer).mutateFn.func1()
	/workspace/src/github.com/bitpoke/wordpress-operator/.work/pkg/pkg/mod/github.com/presslabs/[email protected]/syncer/object.go:107 +0x5a
sigs.k8s.io/controller-runtime/pkg/controller/controllerutil.mutate(0xc00057e480, {{0xc00059adf8, 0xc00007a780}, {0xc00067c090, 0x7ff671b6b5b8}}, {0x176ade0, 0xc00057e480})
	/workspace/src/github.com/bitpoke/wordpress-operator/.work/pkg/pkg/mod/sigs.k8s.io/[email protected]/pkg/controller/controllerutil/controllerutil.go:339 +0x4f
sigs.k8s.io/controller-runtime/pkg/controller/controllerutil.CreateOrUpdate({0x1728018, 0xc00007a780}, {0x1752628, 0xc00021ea00}, {0x176ade0, 0xc00057e480}, 0x203000)
	/workspace/src/github.com/bitpoke/wordpress-operator/.work/pkg/pkg/mod/sigs.k8s.io/[email protected]/pkg/controller/controllerutil/controllerutil.go:211 +0x26b
github.com/presslabs/controller-util/syncer.(*ObjectSyncer).Sync(0xc000380f00, {0x1728018, 0xc00007a780})
	/workspace/src/github.com/bitpoke/wordpress-operator/.work/pkg/pkg/mod/github.com/presslabs/[email protected]/syncer/object.go:75 +0x1b5
github.com/presslabs/controller-util/syncer.Sync({0x1728018, 0xc00007a780}, {0x1741678, 0xc000380f00}, {0x17244d8, 0xc00041cb80})
	/workspace/src/github.com/bitpoke/wordpress-operator/.work/pkg/pkg/mod/github.com/presslabs/[email protected]/syncer/syncer.go:82 +0x6b
github.com/bitpoke/wordpress-operator/pkg/controller/wordpress.(*ReconcileWordpress).sync(0xc0000b5bc0, {0x1728018, 0xc00007a780}, {0xc0012c9d68, 0x4, 0xc00059ade0})
	/workspace/src/github.com/bitpoke/wordpress-operator/pkg/controller/wordpress/wordpress_controller.go:177 +0x94
github.com/bitpoke/wordpress-operator/pkg/controller/wordpress.(*ReconcileWordpress).Reconcile(0xc0000b5bc0, {0x1728018, 0xc00007a780}, {{{0xc00059adf8, 0x14ccb00}, {0xc00059ade0, 0xc000492000}}})
	/workspace/src/github.com/bitpoke/wordpress-operator/pkg/controller/wordpress/wordpress_controller.go:146 +0x4da
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).reconcileHandler(0xc0000d7680, {0x1727f70, 0xc00041cf80}, {0x13f01a0, 0xc0005d2700})
	/workspace/src/github.com/bitpoke/wordpress-operator/.work/pkg/pkg/mod/sigs.k8s.io/[email protected]/pkg/internal/controller/controller.go:298 +0x303
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).processNextWorkItem(0xc0000d7680, {0x1727f70, 0xc00041cf80})
	/workspace/src/github.com/bitpoke/wordpress-operator/.work/pkg/pkg/mod/sigs.k8s.io/[email protected]/pkg/internal/controller/controller.go:253 +0x205
sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).Start.func2.2()
	/workspace/src/github.com/bitpoke/wordpress-operator/.work/pkg/pkg/mod/sigs.k8s.io/[email protected]/pkg/internal/controller/controller.go:214 +0x85
created by sigs.k8s.io/controller-runtime/pkg/internal/controller.(*Controller).Start.func2
	/workspace/src/github.com/bitpoke/wordpress-operator/.work/pkg/pkg/mod/sigs.k8s.io/[email protected]/pkg/internal/controller/controller.go:210 +0x354