Update checkout v6

Author: Thomasdezeeuw

.github/workflows/main.yml

@@ -11,7 +11,7 @@ jobs:
   Test:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v6
     - uses: dtolnay/rust-toolchain@stable
     - name: Install Cargo Hack
       run: cargo install --debug cargo-hack
@@ -20,7 +20,7 @@ jobs:
   Clippy:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v6
     - uses: dtolnay/rust-toolchain@stable
       with:
         components: clippy
@@ -29,7 +29,7 @@ jobs:
   Rustfmt:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v6
     - uses: dtolnay/rust-toolchain@stable
       with:
         components: rustfmt
@@ -38,7 +38,7 @@ jobs:
   Docs:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v6
     - uses: dtolnay/rust-toolchain@stable
     - name: Check docs
       run: RUSTDOCFLAGS="-D warnings" cargo doc --no-deps --all-features