Bump actions/checkout from 3 to 4 (#646)

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] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/IntegrationTest.yml

@@ -17,15 +17,15 @@ jobs:
         package:
           - {user: JuliaManifolds, repo: Manopt.jl}
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: julia-actions/setup-julia@v1
         with:
           version: ${{ matrix.julia-version }}
           arch: x64
       - uses: julia-actions/cache@v1
       - uses: julia-actions/julia-buildpkg@latest
       - name: Clone Downstream
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           repository: ${{ matrix.package.user }}/${{ matrix.package.repo }}
           path: downstream

.github/workflows/ci.yml

@@ -18,7 +18,7 @@ jobs:
           - 'test_lie_groups'
           - 'test_integration'
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: julia-actions/setup-julia@v1
         with:
           version: ${{ matrix.julia-version }}

.github/workflows/clear_preview.yml

@@ -9,7 +9,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout gh-pages branch
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           ref: gh-pages
       - name: Delete preview and history + push changes

.github/workflows/documenter.yml

@@ -11,7 +11,7 @@ jobs:
     runs-on: ubuntu-latest
     if: "contains( github.event.pull_request.labels.*.name, 'preview docs') || github.ref == 'refs/heads/master' || contains(github.ref, 'refs/tags/')"
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: quarto-dev/quarto-actions/setup@v2
         with:
           version: 1.3.361

.github/workflows/format.yml

@@ -10,7 +10,7 @@ jobs:
     name: "Format Check"
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: julia-actions/setup-julia@v1
         with:
           version: 1

.github/workflows/nightly.yml

@@ -14,7 +14,7 @@ jobs:
           - 'test_manifolds'
           - 'test_lie_groups'
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: julia-actions/setup-julia@v1
         with:
           version: nightly