Add OCI source label to image

WHen building the dashboard image with `ko`, add the OCI source label:

`org.opencontainers.image.source=https://$(params.package)`

This is generally useful, and in the case og ghcr.io it lets GitHub
automatically associate the container image with its source repo.

scripts/installer

@@ -30,7 +30,7 @@ EXTERNAL_LOGS=""
 BASE_RELEASE_URL="https://storage.googleapis.com/tekton-releases/dashboard"
 
 # additional options passed to ko resolve
-KO_RESOLVE_OPTIONS=""
+KO_RESOLVE_OPTIONS="--image-label=org.opencontainers.image.source=https://github.com/tektoncd/dashboard"
 PLATFORM=""
 
 # Display a box banner.
@@ -445,7 +445,7 @@ case $1 in
     shift
     ;;
   'release'|r)
-    KO_RESOLVE_OPTIONS="--preserve-import-paths"
+    KO_RESOLVE_OPTIONS="$KO_RESOLVE_OPTIONS --preserve-import-paths"
     ACTION="build"
     shift
     ;;

tekton/publish.yaml

@@ -122,8 +122,9 @@ spec:
         cp ${PROJECT_ROOT}/scripts/installer $OUTPUT_RELEASE_DIR/installer
 
         # build manifests for installer
-        kustomize build overlays/installer/read-only  --load-restrictor LoadRestrictionsNone | ko resolve --platform=$(params.platforms) --preserve-import-paths -t $(params.versionTag) -f - > $OUTPUT_RELEASE_DIR/installer-release.yaml
-        kustomize build overlays/installer/read-write --load-restrictor LoadRestrictionsNone | ko resolve --platform=$(params.platforms) --preserve-import-paths -t $(params.versionTag) -f - > $OUTPUT_RELEASE_DIR/installer-release-full.yaml
+        KO_RESOLVE_IMAGE_LABEL="--image-label=org.opencontainers.image.source=https://$(params.package)"
+        kustomize build overlays/installer/read-only  --load-restrictor LoadRestrictionsNone | ko resolve ${KO_RESOLVE_IMAGE_LABEL} --platform=$(params.platforms) --preserve-import-paths -t $(params.versionTag) -f - > $OUTPUT_RELEASE_DIR/installer-release.yaml
+        kustomize build overlays/installer/read-write --load-restrictor LoadRestrictionsNone | ko resolve ${KO_RESOLVE_IMAGE_LABEL} --platform=$(params.platforms) --preserve-import-paths -t $(params.versionTag) -f - > $OUTPUT_RELEASE_DIR/installer-release-full.yaml
 
         # build pre configured manifests
         ./scripts/installer release --debug              --platform $(params.platforms) --tag $(params.versionTag) --output $OUTPUT_RELEASE_DIR/release.yaml