Port v6 cleanup to v4

[ericsciple]

Auth configuration changed in actions/checkout@v6-beta. This PR ports the cleanup for v6-style configuration to v4.

Otherwise, actions/checkout@v4 will fail if the same repo is already checked out by actions/checkout@v6-beta, in the same job, to the same path. Although this scenario is likely very uncommon, I want to reduce friction for users to move to v6.

For quick mitigation if something goes wrong, ACTIONS_CHECKOUT_SKIP_V6_CLEANUP can be set to 1 or true to skip the new cleanup logic.

Workflow for testing the changes E2E

name: Test Checkout Cleanup

on:
  workflow_dispatch:
  push:
    paths:
      - .github/workflows/test-checkout-cleanup-v4.yml

env:
  ACTIONS_CHECKOUT_SKIP_V6_CLEANUP: true

jobs:
  checkout-v4-then-v6-beta:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout with v4
        uses: actions/checkout@v4
      
      - name: Checkout with v6-beta
        uses: actions/checkout@v6-beta

  checkout-v6-beta-then-v4:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout with v6-beta
        uses: actions/checkout@v6-beta
      
      - name: Checkout with v4
        uses: actions/checkout@v4

  checkout-25-11-clean2-then-v6-beta:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout with 25-11-clean2
        uses: actions/checkout@users/ericsciple/25-11-clean2
      
      - name: Checkout with v6-beta
        uses: actions/checkout@v6-beta

  checkout-v6-beta-then-25-11-clean2:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout with v6-beta
        uses: actions/checkout@v6-beta
      
      - name: Checkout with 25-11-clean2
        uses: actions/checkout@users/ericsciple/25-11-clean2

  checkout-v4-then-v6-beta-submodules:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout with v4
        uses: actions/checkout@v4
        with:
          ref: submodule-test
          submodules: recursive
      
      - name: Checkout with v6-beta
        uses: actions/checkout@v6-beta
        with:
          ref: submodule-test
          submodules: recursive

  checkout-v6-beta-then-v4-submodules:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout with v6-beta
        uses: actions/checkout@v6-beta
        with:
          ref: submodule-test
          submodules: recursive
      
      - name: Checkout with v4
        uses: actions/checkout@v4
        with:
          ref: submodule-test
          submodules: recursive

  checkout-25-11-clean2-then-v6-beta-submodules:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout with 25-11-clean2
        uses: actions/checkout@users/ericsciple/25-11-clean2
        with:
          ref: submodule-test
          submodules: recursive
      
      - name: Checkout with v6-beta
        uses: actions/checkout@v6-beta
        with:
          ref: submodule-test
          submodules: recursive

  checkout-v6-beta-then-25-11-clean2-submodules:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout with v6-beta
        uses: actions/checkout@v6-beta
        with:
          ref: submodule-test
          submodules: recursive
      
      - name: Checkout with 25-11-clean2
        uses: actions/checkout@users/ericsciple/25-11-clean2
        with:
          ref: submodule-test
          submodules: recursive

  checkout-v4-then-v6-beta-submodules-true:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout with v4
        uses: actions/checkout@v4
        with:
          ref: submodule-test
          submodules: true
      
      - name: Checkout with v6-beta
        uses: actions/checkout@v6-beta
        with:
          ref: submodule-test
          submodules: true

  checkout-v6-beta-then-v4-submodules-true:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout with v6-beta
        uses: actions/checkout@v6-beta
        with:
          ref: submodule-test
          submodules: true
      
      - name: Checkout with v4
        uses: actions/checkout@v4
        with:
          ref: submodule-test
          submodules: true

  checkout-25-11-clean2-then-v6-beta-submodules-true:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout with 25-11-clean2
        uses: actions/checkout@users/ericsciple/25-11-clean2
        with:
          ref: submodule-test
          submodules: true
      
      - name: Checkout with v6-beta
        uses: actions/checkout@v6-beta
        with:
          ref: submodule-test
          submodules: true

  checkout-v6-beta-then-25-11-clean2-submodules-true:
    runs-on: ubuntu-latest
    steps:
      - name: Checkout with v6-beta
        uses: actions/checkout@v6-beta
        with:
          ref: submodule-test
          submodules: true
      
      - name: Checkout with 25-11-clean2
        uses: actions/checkout@users/ericsciple/25-11-clean2
        with:
          ref: submodule-test
          submodules: true

Related PRs:

• Persist creds to a separate file #2286
• Port v6 cleanup to v5 #2301

[CosmicJesterX]

hi