feat: allow to spawn and run a local reusable workflow (#1423)

* feat: allow to spawn and run a local reusable workflow

This change contains the ability to parse/plan/run a local
reusable workflow.
There are still numerous things missing:

- inputs
- secrets
- outputs

* feat: add workflow_call inputs

* test: improve inputs test

* feat: add input defaults

* feat: allow expressions in inputs

* feat: use context specific expression evaluator

* refactor: prepare for better re-usability

* feat: add secrets for reusable workflows

* test: use secrets during test run

* feat: handle reusable workflow outputs

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

act/runner/testdata/uses-workflow/local-workflow.yml

@@ -0,0 +1,36 @@
+name: local-reusable-workflows
+on: pull_request
+
+jobs:
+  reusable-workflow:
+    uses: ./.github/workflows/local-reusable-workflow.yml
+    with:
+      string_required: string
+      bool_required: ${{ true }}
+      number_required: 1
+    secrets:
+      secret: keep_it_private
+
+  reusable-workflow-with-inherited-secrets:
+    uses: ./.github/workflows/local-reusable-workflow.yml
+    with:
+      string_required: string
+      bool_required: ${{ true }}
+      number_required: 1
+    secrets: inherit
+
+  output-test:
+    runs-on: ubuntu-latest
+    needs:
+      - reusable-workflow
+      - reusable-workflow-with-inherited-secrets
+    steps:
+      - name: output with secrets map
+        run: |
+          echo reusable-workflow.output=${{ needs.reusable-workflow.outputs.output }}
+          [[ "${{ needs.reusable-workflow.outputs.output == 'string' }}" = "true" ]] || exit 1
+
+      - name: output with inherited secrets
+        run: |
+          echo reusable-workflow-with-inherited-secrets.output=${{ needs.reusable-workflow-with-inherited-secrets.outputs.output }}
+          [[ "${{ needs.reusable-workflow-with-inherited-secrets.outputs.output == 'string' }}" = "true" ]] || exit 1