Add proper support for working-directory & fix command builder (#772)

* fix: align other Docker executors to print action

* fix: formatting

* fix: add proper workdir support

* fix: replace script filepath after slice creation

* fix: match substring so it works for pwsh

+ rename containerPath to scriptPath to reflect what value it contains

pkg/runner/testdata/basic/push.yml

@@ -8,6 +8,7 @@ jobs:
   check:
     runs-on: ubuntu-latest
     steps:
+      - run: '[[ "$(pwd)" == "${GITHUB_WORKSPACE}" ]]'
       - run: echo ${{ env.TEST }} | grep value
       - run: env
       - uses: docker://node:12-buster-slim

pkg/runner/testdata/dir with spaces/push.yml

@@ -0,0 +1,7 @@
+---
+jobs:
+  dir-with-spaces:
+    runs-on: ubuntu-latest
+    steps:
+      - run: echo "$PWD"
+'on': push

pkg/runner/testdata/workdir/push.yml

@@ -1,15 +1,24 @@
-name: workdir
 on: push
 
+defaults:
+  run:
+    working-directory: /tmp
+
 jobs:
   workdir:
     runs-on: ubuntu-latest
+    defaults:
+      run:
+        working-directory: /root
     steps:
-    - run: mkdir -p "${GITHUB_WORKSPACE}/workdir"
-    - run: '[[ "$(pwd)" == "${GITHUB_WORKSPACE}/workdir" ]]'
-      working-directory: workdir
+      - run: '[[ "$(pwd)" == "/root" ]]'
 
-  noworkdir:
+      - run: mkdir -p "${GITHUB_WORKSPACE}/workdir"
+
+      - run: '[[ "$(pwd)" == "${GITHUB_WORKSPACE}/workdir" ]]'
+        working-directory: workdir
+
+  top-level-workdir:
     runs-on: ubuntu-latest
     steps:
-      - run: '[[ "$(pwd)" == "${GITHUB_WORKSPACE}" ]]'
+      - run: '[[ "$(pwd)" == "/tmp" ]]'