Update actions/checkout action to v6

Author: renovate[bot]

.github/workflows/goreleaser.yaml

@@ -13,7 +13,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
-        uses: actions/checkout@v2
+        uses: actions/checkout@v6
         with:
           fetch-depth: 0
 

.github/workflows/rust.yaml

@@ -7,7 +7,7 @@ jobs:
     name: Test Suite
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v6
       - uses: actions-rs/toolchain@v1
         with:
           profile: minimal
@@ -22,7 +22,7 @@ jobs:
     name: Rustfmt
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v6
       - uses: actions-rs/toolchain@v1
         with:
           profile: minimal
@@ -38,7 +38,7 @@ jobs:
     name: Clippy
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v6
       - uses: actions-rs/toolchain@v1
         with:
           profile: minimal