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

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>

Author: dependabot[bot]

.github/workflows/mypy.yml

@@ -16,7 +16,7 @@ jobs:
     name: Python ${{ matrix.python-version }} sample
 
     steps:
-    - uses: actions/checkout@v6
+    - uses: actions/checkout@v7
     - name: Set up Python
       uses: actions/setup-python@v6
       with:

.github/workflows/release.yml

@@ -16,7 +16,7 @@ jobs:
     permissions:
       id-token: write  # IMPORTANT: this permission is mandatory for trusted publishing
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
         with:
           fetch-depth: 0
       - name: Install Poetry

.github/workflows/test_public_interface.yml

@@ -17,7 +17,7 @@ jobs:
     name: Python ${{ matrix.python-version }} sample
 
     steps:
-    - uses: actions/checkout@v6
+    - uses: actions/checkout@v7
     - name: Set up Python
       uses: actions/setup-python@v6
       with: