fix: Fix secret reference to Rancher cloud credential

[yiannistri]

What this PR does / why we need it:

This PR fixes the secret reference to Rancher cloud credential.

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #1978

Special notes for your reviewer:

Running

helm template rancher-turtles-providers ./charts/rancher-turtles-providers --set providers.infrastructureAWS.enabled=true,providers.infrastructureAWS.credentials.name=bar

results in

apiVersion: turtles-capi.cattle.io/v1alpha1
kind: CAPIProvider
metadata:
  name: aws
  namespace: capa-system
spec:
  name: aws
  type: infrastructure
  enableAutomaticUpdate: true
  variables:
    AWS_B64ENCODED_CREDENTIALS: ""
  credentials:
    rancherCloudCredential: bar

In this case the namespace that will be used to lookup the secret is cattle-global-data.

Running

helm template rancher-turtles-providers ./charts/rancher-turtles-providers --set providers.infrastructureAWS.enabled=true,providers.infrastructureAWS.credentials.name=bar,providers.infrastructureAWS.credentials.namespace=foo

results in

apiVersion: turtles-capi.cattle.io/v1alpha1
kind: CAPIProvider
metadata:
  name: aws
  namespace: capa-system
spec:
  name: aws
  type: infrastructure
  enableAutomaticUpdate: true
  variables:
    AWS_B64ENCODED_CREDENTIALS: ""
  credentials:
    rancherCloudCredentialNamespaceName: foo:bar

Checklist:

• squashed commits into logical changes
• includes documentation
• adds unit tests
• adds or updates e2e tests

[anmazzotti]

All good, but the schema is not updated accordingly.

[salasberryfin]

Thanks @yiannistri. LGTM pending the schema update.