Provisioning: Add Validation and Mutation for Connection resource (#115596)

* WIP: mutator added, start working on validator

* first validator iteration

* second validator iteration

* wip: working on integration tests

* re-working mutation and validation, using Connection interface

* fixing some rebase things

* fixing integration tests

* formatting

* fixing unit tests

* k8s codegen

* linting

* moving tests which are available only for enterprise

* addressing comments: using repo config for connections, updating tests

* addressing comments: adding some more info in the app and installation

* fixing app data

* addressing comments: updating connection implementation

* addressing comments

* formatting

* fixing tests

pkg/tests/apis/openapi_snapshots/provisioning.grafana.app-v0alpha1.json

@@ -4559,7 +4559,7 @@
               }
             ]
           },
-          "webhook": {
+          "token": {
             "description": "Token is the reference of the token used to act as the Connection. This value is stored securely and cannot be read back",
             "default": {},
             "allOf": [