Remove dependency on the runner's volume (#244)

* bump actions

* experiment using init container to prepare working environment

* rm script before continuing

* fix

* Update packages/k8s/src/hooks/run-script-step.ts

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>

* leverage exec stat instead of printf

* npm update

* document the new constraint

---------

Co-authored-by: DenisPalnitsky <DenisPalnitsky@users.noreply.github.com>

examples/extension.yaml

@@ -4,9 +4,6 @@ metadata:
   labels:
     labeled-by: "extension"
 spec:
-  securityContext:
-    runAsUser: 1000
-    runAsGroup: 3000
   restartPolicy: Never
   containers:
   - name: $job # overwrites job container