Upgrade checkout action from v4 to v6

Author: bashandbone

.github/workflows/release.yml

@@ -52,7 +52,7 @@ jobs:
             os: windows-latest
             build-tool: cargo
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
       - uses: Swatinem/rust-cache@v2
         with:
           shared-key: rust-${{ matrix.target }}
@@ -71,7 +71,7 @@ jobs:
       needs: [build, publish]
       runs-on: ubuntu-latest
       steps:
-          - uses: actions/checkout@v4
+          - uses: actions/checkout@v6
 
           - name: Download all artifacts
             uses: actions/download-artifact@v4