Bump actions/checkout from 4 to 7

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>

Author: dependabot[bot]

.github/workflows/check.yml

@@ -25,7 +25,7 @@ jobs:
     runs-on: ubuntu-latest
     name: stable / fmt
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
         with:
           submodules: true
       - name: Install stable
@@ -46,7 +46,7 @@ jobs:
         # Get early warning of new lints which are regularly introduced in beta channels.
         toolchain: [stable, beta]
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
         with:
           submodules: true
       - name: Install ${{ matrix.toolchain }}
@@ -63,7 +63,7 @@ jobs:
     runs-on: ubuntu-latest
     name: semver
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
         with:
           submodules: true
       - name: Install stable
@@ -79,7 +79,7 @@ jobs:
     runs-on: ubuntu-latest
     name: nightly / doc
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
         with:
           submodules: true
       - name: Install nightly
@@ -94,7 +94,7 @@ jobs:
     runs-on: ubuntu-latest
     name: ubuntu / stable / features
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
         with:
           submodules: true
       - name: Install stable
@@ -115,7 +115,7 @@ jobs:
         msrv: ["1.88.0"] # 2024 edition requires 1.85
     name: ubuntu / ${{ matrix.msrv }}
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
         with:
           submodules: true
       - name: Install ${{ matrix.msrv }}
@@ -128,7 +128,7 @@ jobs:
     runs-on: ubuntu-latest
     name: stable / examples
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
         with:
           submodules: true
       - uses: dtolnay/rust-toolchain@stable

.github/workflows/scheduled.yml

@@ -19,7 +19,7 @@ jobs:
     runs-on: ubuntu-latest
     name: ubuntu / nightly
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
         with:
           submodules: true
       - name: Install nightly
@@ -42,7 +42,7 @@ jobs:
     # just redo what happened in the regular test job. Unfortunately, hashFiles only works in if on
     # steps, so we repeat it.
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
         with:
           submodules: true
       - name: Install beta

.github/workflows/test.yml

@@ -26,7 +26,7 @@ jobs:
         # toolchain
         toolchain: [stable, beta]
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
         with:
           submodules: true
       - name: Install ${{ matrix.toolchain }}
@@ -69,7 +69,7 @@ jobs:
     runs-on: ubuntu-latest
     name: ubuntu / stable / direct-minimal-versions
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
         with:
           submodules: true
       - name: Install stable
@@ -97,7 +97,7 @@ jobs:
       #   if: runner.os == 'Windows'
       # - run: vcpkg install openssl:x64-windows-static-md
       #   if: runner.os == 'Windows'
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v7
         with:
           submodules: true
       - name: Install stable