chore(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/docs.yml

@@ -34,7 +34,7 @@ jobs:
     permissions:
       contents: read
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
 
       - uses: actions/setup-python@v6
         with:

.github/workflows/release.yml

@@ -20,7 +20,7 @@ jobs:
       contents: write
 
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
 
       - name: Verify Cargo.toml version matches release tag
         run: |

.github/workflows/rust.yml

@@ -20,7 +20,7 @@ jobs:
     permissions:
       contents: read
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
 
       - name: Install Rust (stable + clippy)
         uses: dtolnay/rust-toolchain@stable
@@ -50,7 +50,7 @@ jobs:
     permissions:
       contents: read
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
       - name: Install Rust (stable + rustfmt)
         uses: dtolnay/rust-toolchain@stable
         with:
@@ -68,7 +68,7 @@ jobs:
       pull-requests: write
       checks: write
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
       - uses: rustsec/audit-check@v2
         with:
           token: ${{ secrets.GITHUB_TOKEN }}
@@ -79,7 +79,7 @@ jobs:
     permissions:
       contents: read
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
 
       - name: Install Rust (stable + llvm-tools)
         uses: dtolnay/rust-toolchain@stable