Bump actions/checkout from 5 to 6 (#32)

Author: dependabot[bot]

.github/workflows/release.yml

@@ -11,7 +11,7 @@ jobs:
     permissions:
       id-token: write
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - uses: rust-lang/crates-io-auth-action@v1
       id: auth
     - run: cargo publish
@@ -22,7 +22,7 @@ jobs:
   release:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: Generate release body
       id: create_release_body
       run: |

.github/workflows/test.yml

@@ -22,7 +22,7 @@ jobs:
     name: Check Clippy and rustfmt
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: dtolnay/rust-toolchain@master
         with:
           toolchain: stable
@@ -38,7 +38,7 @@ jobs:
     env:
       RUSTDOCFLAGS: "-Dwarnings --cfg docsrs -Zunstable-options --generate-link-to-definition"
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Install toolchain
         uses: dtolnay/rust-toolchain@master
         with:
@@ -80,7 +80,7 @@ jobs:
             variant: minimal_versions
 
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Not MSRV
         if: ${{ matrix.variant != 'MSRV' }}
         run: cargo generate-lockfile --ignore-rust-version
@@ -109,7 +109,7 @@ jobs:
             toolchain: stable
 
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Install toolchain
         uses: dtolnay/rust-toolchain@master
         with:
@@ -130,7 +130,7 @@ jobs:
   test-miri:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Install toolchain
         run: |
           rustup toolchain install nightly --component miri
@@ -143,7 +143,7 @@ jobs:
   test-no-std:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Install toolchain
         uses: dtolnay/rust-toolchain@nightly
         with:
@@ -154,7 +154,7 @@ jobs:
   test-ios:
     runs-on: macos-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Install toolchain
         uses: dtolnay/rust-toolchain@nightly
         with: