chore: Bump actions/checkout from 5 to 6 in the github-actions group (#134)

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/nightly.yaml

@@ -9,7 +9,7 @@ jobs:
     name: Check for unused dependencies
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: taiki-e/install-action@v2
         with:
           tool: just

.github/workflows/pr.yaml

@@ -6,7 +6,7 @@ jobs:
   test:
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: taiki-e/install-action@v2
         with:
           tool: just
@@ -23,7 +23,7 @@ jobs:
   lint:
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: taiki-e/install-action@v2
         with:
           tool: just
@@ -46,7 +46,7 @@ jobs:
   msrv-check:
     runs-on: ubuntu-24.04
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: taiki-e/install-action@v2
         with:
           tool: just, cargo-binstall

.github/workflows/release.yaml

@@ -15,7 +15,7 @@ jobs:
     runs-on: ubuntu-24.04
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
         with:
           fetch-depth: 0
       - uses: taiki-e/install-action@v2