Bump actions/checkout from 3 to 4

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] <support@github.com>

Author: dependabot[bot]

.github/workflows/main.yml

@@ -68,7 +68,7 @@ jobs:
             rust: stable-x86_64
             target: x86_64-pc-windows-msvc
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: Install Rust (rustup)
       run: |
         set -euxo pipefail
@@ -96,7 +96,7 @@ jobs:
     name: Test CUDA support
     runs-on: ubuntu-20.04
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: Install cuda-minimal-build-11-8
       shell: bash
       run: |
@@ -117,7 +117,7 @@ jobs:
       matrix:
         os: [ubuntu-latest, windows-latest]
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: Install Rust
       run: |
         rustup toolchain install 1.46.0 --no-self-update --profile minimal
@@ -129,7 +129,7 @@ jobs:
     name: Rustfmt
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - name: Install Rust
       run: |
         rustup toolchain install stable --no-self-update --profile minimal --component rustfmt