implement volume mount for container job (#1101)

* implement volume mount for container job

* Update pkg/runner/run_context.go

Co-authored-by: Ryan <me@hackerc.at>

* add tests for container volume mount options

* remove unused code

* prefer if-else instead of if-continue

* remove continue

* add some tests

Co-authored-by: Ryan <me@hackerc.at>
Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>

pkg/model/testdata/container-volumes/push.yml

@@ -0,0 +1,19 @@
+name: Job Container
+on: push
+
+jobs:
+  with-volumes:
+    runs-on: ubuntu-latest
+    container:
+      image: node:16-buster-slim
+      volumes:
+        - my_docker_volume:/path/to/volume
+        - /path/to/nonexist/directory
+        - /proc/sys/kernel/random/boot_id:/current/boot_id
+    steps:
+      - run: |
+          set -e
+          test -d /path/to/volume
+          test "$(cat /proc/sys/kernel/random/boot_id)" = "$(cat /current/boot_id)"
+          test -d /path/to/nonexist/directory
+