[TT-11737] [PoC] custom Tyk directive @uppercase

[buraksezer]

PoC for TT-11737. See https://github.com/TykTechnologies/graphql-go-tools/pull/428 for details.

[github-actions[bot]]

API Changes

--- prev.txt	2024-04-12 12:49:08.806463556 +0000
+++ current.txt	2024-04-12 12:49:04.426421816 +0000
@@ -2019,6 +2019,16 @@
 
 func (s *Supergraph) EngineConfig() (*graphql.EngineV2Configuration, error)
 
+type ToUpperDirective struct{}
+
+func NewToUpperDirective() *ToUpperDirective
+
+func (t *ToUpperDirective) DataType() string
+
+func (t *ToUpperDirective) Execute(input []byte) ([]byte, error)
+
+func (t *ToUpperDirective) Name() string
+
 type UniversalDataGraph struct {
 	ApiDefinition   *apidef.APIDefinition
 	HttpClient      *http.Client