fix: step container workdir and mounts (#93)

* fix: step container workdir and mounts
* avoid perm issues and do not mount tool_cache

pkg/runner/testdata/docker-action-host-env/push.yml

@@ -0,0 +1,15 @@
+name: Hello World Docker Action Workflow
+
+on: [push]
+
+jobs:
+  hello_world_job:
+    runs-on: self-hosted
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+
+      - name: Run Hello World Docker Action
+        uses: ./docker-action-host-env/action
+        with:
+          who-to-greet: "GitHub"