Tag image as latest only when releasing the latest tag

Signed-off-by: dwertent <david.wertenteil@kaleido.io>

Author: dwertent

.github/workflows/docker_release.yml

@@ -5,8 +5,28 @@ on:
     types: [released, prereleased]
 
 jobs:
+  fetch-latest-tag:
+    runs-on: ubuntu-latest
+    outputs:
+      latest_tag: ${{ steps.get_latest_tag.outputs.latest_tag }}
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v3
+        with:
+          fetch-depth: 0
+
+      - name: Fetch all tags
+        run: git fetch --tags
+
+      - name: Get the latest tag
+        id: get_latest_tag
+        run: |
+          latest_tag=$(git tag -l | sort -V | tail -n 1)
+          echo "::set-output name=latest_tag::${latest_tag}"
+
   docker:
     runs-on: ubuntu-latest
+    needs: fetch-latest-tag
     permissions:
       contents: read
       packages: write
@@ -30,7 +50,7 @@ jobs:
           password: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Set latest tag
-        if: github.event.action == 'released'
+        if: github.event.action == 'released' && github.ref_name == needs.fetch-latest-tag.outputs.latest_tag
         run: |
           echo "DOCKER_TAGS=${{ env.DOCKER_TAGS }},ghcr.io/${{ github.repository }}:latest" >> $GITHUB_ENV