Add workflow to clear caches

Author: jan-tennert

.github/workflows/cache.yml

@@ -0,0 +1,16 @@
+name: Clear all Github actions caches
+on:
+  workflow_dispatch:
+
+permissions:
+  actions: write
+
+jobs:
+  clear-cache:
+    name: Delete all caches
+    runs-on: ubuntu-20.04
+    steps:
+      - name: Clear caches
+        uses: easimon/wipe-cache@main
+        with:
+          github-token: ${{ secrets.GITHUB_TOKEN }}