Bump actions/checkout from 3 to 4 (#22)

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

.github/workflows/ci.yml

@@ -24,7 +24,7 @@ jobs:
       rust-versions: ${{ steps.definitions.outputs.versions }}
       msrv: ${{ steps.definitions.outputs.msrv }}
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - name: Evaluate definitions
         id: definitions
         run: |
@@ -37,7 +37,7 @@ jobs:
   rustfmt:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - name: Install rust toolchain
         id: toolchain
@@ -52,7 +52,7 @@ jobs:
   clippy:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - name: Install rust toolchain
         id: toolchain
@@ -69,7 +69,7 @@ jobs:
   udeps:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - name: Install toolchain
         id: toolchain
@@ -96,7 +96,7 @@ jobs:
         rust: ${{ fromJson(needs.env.outputs.rust-versions) }}
         os: [ubuntu-latest, macOS-latest, windows-latest]
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
           lfs: true
 
@@ -120,7 +120,7 @@ jobs:
       matrix:
         crate: [bach]
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - name: Install toolchain
         id: toolchain