Ability to add a step to a job

[TWiStErRob]

Feature request
I would like to insert a step into a workflow from a test.

I think this syntax would work:

      mockSteps: {
        "job-name": [
          {
            before: N, // or after: N,
            mockWith: {...}
          }
        ]
      }

Additional context
When testing local actions, we need to clone the MockGithub repository, but in production we don't need this and we don't want to create noise in the real executions by doing an if: ... or having a placeholder step to replace with mock.

Workaround
For now I did this:

      # "Placeholder for test to hook into."
      - id: checkout
        run: |
          true

+

      mockSteps: {
        "job-name": [
          {
            id: "checkout",
            mockWith: {
              name: "Checkout (test only)"
              uses: "actions/checkout@v4",
              run: undefined,
            }
          }
        ]
      }

Proposed solution

No yaml changes.
+

      mockSteps: {
        "job-name": [
          {
            before: 0,
            mockWith: {
              name: "Checkout (test only)"
              uses: "actions/checkout@v4",
            }
          }
        ]
      }