Use unique cache key for issue check support

.github/actions/init-python/action.yml

@@ -36,7 +36,7 @@ runs:
       uses: actions/cache@v4
       with:
         path: .venv
-        key: python_venv-${{ inputs.cache-key }}-${{ hashFiles('scripts/pyproject.toml') }}
+        key: python-venv-${{ inputs.cache-key }}-${{ hashFiles('scripts/pyproject.toml') }}
 
     # Use bash if to make output clearer in case of skipping.
     - name: Setup Python venv

.github/workflows/issue-check-support.yml

@@ -22,7 +22,7 @@ jobs:
       - name: Setup Python venv
         uses: ./.github/actions/init-python
         with:
-          cache-key: "ubuntu-latest"
+          cache-key: "check-support"
 
       - name: Check issue
         id: issue-check