ci: bump actions/checkout from 4 to 7 (#2)

Bumps [actions/checkout](https://github.com/actions/checkout) from 4 to 7.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v4...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/ci.yml

@@ -22,7 +22,7 @@ jobs:
     name: fmt, clippy, test, docs
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
       - uses: dtolnay/rust-toolchain@stable
         with:
           components: rustfmt, clippy
@@ -43,7 +43,7 @@ jobs:
     name: no_std build (bare metal)
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
       - uses: dtolnay/rust-toolchain@stable
         with:
           targets: thumbv7em-none-eabihf
@@ -54,15 +54,15 @@ jobs:
     name: minimum supported Rust (1.81)
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
       - uses: dtolnay/rust-toolchain@1.81.0
       - run: cargo build --all-features
 
   conformance:
     name: Conformance vectors
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
       - uses: dtolnay/rust-toolchain@stable
       - name: Download shared conformance vectors
         run: curl -sSfL -o vectors.jsonl https://raw.githubusercontent.com/firechip/cobs-conformance/v1.0.0/vectors/vectors.jsonl

.github/workflows/commit-lint.yml

@@ -12,7 +12,7 @@ jobs:
     name: Conventional Commits
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
         with:
           fetch-depth: 0
       - name: Check commit subjects follow Conventional Commits

.github/workflows/release.yml

@@ -22,7 +22,7 @@ jobs:
       id-token: write # required for the OIDC token exchange
       contents: read
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@v7
       - uses: dtolnay/rust-toolchain@stable
       - name: Verify before publishing
         run: |