Move the Dashboard nightly image to GHCR

Publish the Dashboard nightly release image to ghcr.io

Old images were at:
  `gcr.io/tekton-nightly/github.com/tektoncd/dashboard/cmd/<image-name>`

With this change they will now be at:
  `ghcr.io/tektoncd/dashboard/<image-name>`

tekton/cronjobs/dogfooding/releases/dashboard-nightly/cronjob.yaml

@@ -14,6 +14,14 @@ spec:
             env:
               - name: PROJECT_NAME
                 value: dashboard
+              - name: CR_URI
+                value: ghcr.io
+              - name: CR_PATH
+                value: tektoncd/dashboard
+              - name: CR_REGIONS
+                value: ""
+              - name: CR_USER
+                value: tekton-robot
           initContainers:
           - name: git
             env:

tekton/resources/nightly-release/overlays/dashboard/template.yaml

@@ -21,10 +21,18 @@
           value: $(tt.params.imageRegistry)
         - name: imageRegistryPath
           value: $(tt.params.imageRegistryPath)
+        - name: imageRegistryUser
+          value: $(tt.params.imageRegistryUser)
+        - name: imageRegistryRegions
+          value: $(tt.params.imageRegistryRegions)
         - name: versionTag
           value: $(tt.params.versionTag)
         - name: serviceAccountPath
           value: release.json
+        - name: serviceAccountImagesPath
+          value: credentials
+        - name: koExtraArgs
+          value: ""
         workspaces:
           - name: workarea
             volumeClaimTemplate:
@@ -37,3 +45,6 @@
           - name: release-secret
             secret:
               secretName: release-secret
+          - name: release-images-secret
+            secret:
+              secretName: ghcr-creds