Bump the actions group with 1 update

Bumps the actions group with 1 update: [actions/checkout](https://github.com/actions/checkout).

- [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
  dependency-group: actions
...

Signed-off-by: dependabot[bot] <support@github.com>

.github/workflows/check.yml

@@ -13,7 +13,7 @@ jobs:
     name: fmt (stable)
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
           submodules: true
       - name: Install stable
@@ -34,7 +34,7 @@ jobs:
       matrix:
         toolchain: [stable, beta]
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
           submodules: true
       - name: Install ${{ matrix.toolchain }}
@@ -53,7 +53,7 @@ jobs:
     runs-on: ubuntu-latest
     name: doc (nightly)
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
           submodules: true
       - name: Install nightly
@@ -69,7 +69,7 @@ jobs:
     name: hack (stable)
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
           submodules: true
       - name: Install stable
@@ -90,7 +90,7 @@ jobs:
       matrix:
         msrv: [1.56.1]
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
           submodules: true
       - name: Install ${{ matrix.msrv }}

.github/workflows/docker.yml

@@ -15,7 +15,7 @@ jobs:
     name: docker
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
           submodules: true
       - name: Docker meta

.github/workflows/test.yml

@@ -16,7 +16,7 @@ jobs:
       matrix:
         toolchain: [stable, beta]
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
           submodules: true
       - name: Install ${{ matrix.toolchain }}
@@ -37,7 +37,7 @@ jobs:
     runs-on: ubuntu-latest
     name: coverage (stable)
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
         with:
           submodules: true
       - name: Install stable