build(deps): Bump actions/checkout from 3 to 4

Bumps [actions/checkout](https://github.com/actions/checkout) from 3 to 4.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v3...v4)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

.github/workflows/pull_request.yml

@@ -19,7 +19,7 @@ jobs:
       # Clone timefold-solver
       # Need to check for stale repo, since Github is not aware of the build chain and therefore doesn't automate it.
       - name: Checkout timefold-solver to access the scripts
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           path: './timefold-solver'
           repository: 'TimefoldAI/timefold-solver'
@@ -34,7 +34,7 @@ jobs:
           ./timefold-solver/.github/scripts/check_chain_repo.sh
           rm -rf ./timefold-solver
       - name: Checkout the proper timefold-solver branch
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           repository: ${{ env.TARGET_CHAIN_USER }}/${{ env.TARGET_CHAIN_REPO }}
           ref: ${{ env.TARGET_CHAIN_BRANCH }}
@@ -51,7 +51,7 @@ jobs:
       # Clone timefold-quickstarts
       # No need to check for stale repo, as Github merges the main repo into the fork automatically.
       - name: Checkout timefold-quickstarts
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           path: './timefold-quickstarts'
 

.github/workflows/pull_request_gradle.yml

@@ -18,7 +18,7 @@ jobs:
       # Clone timefold-solver
       # Need to check for stale repo, since Github is not aware of the build chain and therefore doesn't automate it.
       - name: Checkout timefold-solver to access the scripts
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           path: './timefold-solver'
           repository: 'TimefoldAI/timefold-solver'
@@ -33,7 +33,7 @@ jobs:
           ./timefold-solver/.github/scripts/check_chain_repo.sh
           rm -rf ./timefold-solver
       - name: Checkout the proper timefold-solver branch
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           repository: ${{ env.TARGET_CHAIN_USER }}/${{ env.TARGET_CHAIN_REPO }}
           ref: ${{ env.TARGET_CHAIN_BRANCH }}
@@ -50,7 +50,7 @@ jobs:
       # Clone timefold-quickstarts
       # No need to check for stale repo, as Github merges the main repo into the fork automatically.
       - name: Checkout timefold-quickstarts
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           path: './timefold-quickstarts'