chore(deps): update actions/checkout action to v6

Author: renovate[bot]

.github/workflows/ci.yml

@@ -14,7 +14,7 @@ jobs:
       matrix:
         os: [ubuntu-latest, macOS-latest, windows-latest]
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: dtolnay/rust-toolchain@stable
       - run: cargo check
 
@@ -25,15 +25,15 @@ jobs:
       matrix:
         os: [ubuntu-latest, macOS-latest, windows-latest]
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: dtolnay/rust-toolchain@stable
       - run: cargo test
 
   fmt:
     name: cargo fmt --all -- --check
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: dtolnay/rust-toolchain@stable
       - run: rustup component add rustfmt
       - run: cargo fmt --all -- --check
@@ -45,7 +45,7 @@ jobs:
       matrix:
         os: [ubuntu-latest, macOS-latest, windows-latest]
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: dtolnay/rust-toolchain@stable
       - run: rustup component add clippy
       - run: cargo clippy --all-targets -- -D warnings
@@ -57,7 +57,7 @@ jobs:
       matrix:
         os: [ubuntu-latest, macOS-latest, windows-latest]
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: dtolnay/rust-toolchain@stable
         with:
           toolchain: ${{ env.RUST_MIN_SRV }}
@@ -74,7 +74,7 @@ jobs:
           - { os: macos-latest   , features: macos }
           - { os: windows-latest , features: windows }
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: Initialize workflow variables
       id: vars
       shell: bash
@@ -152,7 +152,7 @@ jobs:
     env:
       RUN_FOR: 60
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - uses: dtolnay/rust-toolchain@nightly
     - name: Install `cargo-fuzz`
       run: cargo install cargo-fuzz