build(deps): bump actions/checkout from 6 to 7 (#137)

Bumps [actions/checkout](https://github.com/actions/checkout) from 6 to 7.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v6...v7)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '7'
  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>

Author: dependabot[bot]

.github/workflows/build-sdist.yml

@@ -27,7 +27,7 @@ jobs:
     runs-on: ${{ matrix.os }}
 
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
 
       - uses: actions/setup-python@v6
         name: Set up Python ${{ matrix.python }}

.github/workflows/build-wheels.yml

@@ -26,7 +26,7 @@ jobs:
     runs-on: ${{ matrix.os }}
 
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
 
       - name: Install SWIG
         if: runner.os == 'Windows'

.github/workflows/release.yml

@@ -32,7 +32,7 @@ jobs:
       contents: write
 
     steps:
-    - uses: actions/checkout@v6
+    - uses: actions/checkout@v7
 
     # Download all artifacts to the same directory (sdist and wheels).
     - uses: actions/download-artifact@v8

.github/workflows/versions.yml

@@ -25,7 +25,7 @@ jobs:
       swigplk_version: ${{ steps.swiglpk.outputs.swigplk_version }}
 
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
 
       - name: Set up Python ${{ matrix.python-version }}
         uses: actions/setup-python@v6