fix: ensure all post steps are executed (#1286)

This fixes an issue in the chain of post steps introduced
while updating the step-logger for composite actions.

It includes a test case so we make sure this does not happen
again.

pkg/runner/testdata/ensure-post-steps/push.yml

@@ -0,0 +1,8 @@
+name: test
+on: push
+jobs:
+  second-post-step-should-fail:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v3
+      - uses: ./ensure-post-steps/action-composite/