chore(ci): automatically update cache key on format change

Signed-off-by: Stavros Kois <47820033+stavros-k@users.noreply.github.com>

.github/workflows/charts-release.yaml

@@ -20,12 +20,20 @@ jobs:
           token: ${{ secrets.BOT_TOKEN }}
           fetch-depth: 0
 
+      - name: Get Changelog Format Version
+        shell: bash
+        run: |
+          ver=$(./charttool genchangelog format-version)
+          key="changelog-json-format-$ver"
+          echo "Cache Key is: $key"
+          echo "CHANGELOG_CACHE_KEY=$key" >> $GITHUB_ENV          
+
       - name: Cache Changelog
         id: cache-changelog
         uses: actions/cache@0c45773b623bea8c8e75f6c82b208c3cf94ea4f9 # v4
         with:
           path: changelog.json.gz
-          key: changelog-json-format-2
+          key: ${{ env.CHANGELOG_CACHE_KEY }}
 
       - name: Generate Changelog
         shell: bash