local: spin app cannot write to wasmtime cache

[bacongobbler]

Looking at the job logs for a spin app spawned with Hippo, I see this:

2022-06-14T19:09:08.927603Z  WARN build: wasmtime_cache: Failed to write file with rename, lock path: /root/.cache/wasmtime/modules/wasmtime-/IdieBqaKdhv0ZMK-q-zCxIOJvOpkt-3GMaJI50WMLIc.wip-atomic-write-mod, target path: /root/.cache/wasmtime/modules/wasmtime-/IdieBqaKdhv0ZMK-q-zCxIOJvOpkt-3GMaJI50WMLIc, err: No such file or directory (os error 2)    

/root/.cache/wasmtime does not exist on my machine.