Update actions/checkout action to v6

Author: renovate[bot]

.github/workflows/build.yml

@@ -21,7 +21,7 @@ jobs:
     name: Run linting/pre-commit checks
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - uses: actions/setup-python@v6
         with:
           python-version: '3.10'
@@ -41,7 +41,7 @@ jobs:
     env:
       PLATFORM: ${{ matrix.platform }}
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: Install the latest version of uv
       uses: astral-sh/setup-uv@v7
       with:
@@ -103,7 +103,7 @@ jobs:
     name: Upload coverage reports to Codecov
     steps:
       - name: Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - name: Download artifacts
         uses: actions/download-artifact@v4
         with:

.github/workflows/full_cluster_tests.yml

@@ -34,7 +34,7 @@ jobs:
     name: Upload coverage reports to Codecov
     steps:
       - name: Checkout
-        uses: actions/checkout@v5
+        uses: actions/checkout@v6
       - name: Download artifacts
         uses: actions/download-artifact@v4
       - name: Upload coverage reports to Codecov

.github/workflows/publish.yml

@@ -14,7 +14,7 @@ jobs:
     runs-on: ${{ matrix.os }}
     environment: release
     steps:
-    - uses: actions/checkout@v5
+    - uses: actions/checkout@v6
     - name: Install the latest version of uv
       uses: astral-sh/setup-uv@v7
       with:

.github/workflows/testing.yml

@@ -31,7 +31,7 @@ jobs:
             # that we don't have to go through 2FA on DRAC clusters.
             ssh -O check -oStrictHostKeyChecking=no ${{ inputs.cluster }}
 
-      - uses: actions/checkout@v5
+      - uses: actions/checkout@v6
       - name: Install the latest version of uv
         uses: astral-sh/setup-uv@v7
         with: