update buildpack workflow example (#21)

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I've faced some errors and bugs when adapting the
cloudrun-buildpacks.yml workflow for my buildpacks usecase. This PR aims
to fix the bugs and update the actions used to their latest versions.

* Update cloudrun-buildpacks.yml file to use the latest github actions
* Setting up the buildpack using the official setup-tools & setup-packs
github actions.
* Fix the bugs in the pack publish commands

Author: kkram01

workflows/deploy-cloudrun/cloudrun-buildpacks.yml

@@ -111,20 +111,20 @@ jobs:
       #   password: ${{ secrets.GCP_CREDENTIALS }}
 
       # BEGIN - Pack download, build and publish
-
+      - id: setup-tools
+        uses: buildpacks/github-actions/[email protected]
+      - id: setup-pack
+        uses: buildpacks/github-actions/[email protected]
       # Build and publish image to Artifact Registry
       - name: Build and Publish with Buildpacks
-        uses: buildpacks/github-actions/[email protected]
         run: |-
           pack config default-builder gcr.io/buildpacks.builder:v1
-          pack build ${{ env.SOURCE_CODE_DIRECTORY }}
-          pack --publish  ${{ env.GAR_LOCATION }}-docker.pkg.dev/${{ env.PROJECT_ID }}/${{ env.REPOSITORY }}/${{ env.SERVICE }}:${{ github.sha }}
-
+          pack build ${{ env.GAR_LOCATION }}-docker.pkg.dev/${{ env.PROJECT_ID }}/${{ env.REPOSITORY }}/${{ env.SERVICE }}:${{ github.sha }} --path=${{ env.SOURCE_DIRECTORY }} --publish
       # END - Docker auth, pack download, buildpack build and publish
 
       - name: Deploy to Cloud Run
         id: deploy
-        uses: google-github-actions/deploy-cloudrun@v0
+        uses: google-github-actions/deploy-cloudrun@v2
         with:
           service: ${{ env.SERVICE }}
           region: ${{ env.REGION }}