Bump actions/checkout from 5 to 6

Bumps [actions/checkout](https://github.com/actions/checkout) from 5 to 6.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@v5...v6)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -21,7 +21,7 @@ jobs:
             features: hashbrown
     runs-on: ${{ matrix.target.os }}
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: dtolnay/rust-toolchain@nightly
       - name: Generate lockfile with minimal dependency versions
         run: cargo +nightly generate-lockfile -Zminimal-versions
@@ -49,7 +49,7 @@ jobs:
           - visualizer,std
     runs-on: ${{ matrix.target.os }}
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Cargo test all targets
         run: cargo test --workspace --all-targets --no-default-features --features ${{ matrix.target.backend }},${{ matrix.features }}
       - name: Cargo test docs
@@ -59,7 +59,7 @@ jobs:
     name: Rustfmt
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Cargo fmt
         run: cargo fmt --all -- --check
 
@@ -81,7 +81,7 @@ jobs:
           - visualizer,std
     runs-on: ${{ matrix.target.os }}
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Cargo clippy
         run: cargo clippy --workspace --all-targets --no-default-features --features ${{ matrix.target.backend }},${{ matrix.features }} -- -D warnings
 
@@ -95,14 +95,14 @@ jobs:
     env:
       RUSTDOCFLAGS: -Dwarnings
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Build documentation
         run: cargo doc --no-deps --workspace --all-features --document-private-items
 
   readme:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Use cached cargo-readme
         uses: actions/cache@v4
         id: cargo-readme-cache

.github/workflows/publish.yaml

@@ -10,6 +10,6 @@ jobs:
     if: github.repository_owner == 'Traverse-Research'
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Publish
         run: cargo publish --token ${{ secrets.cratesio_token }}