Update actions/checkout action to v5

Author: renovate[bot]

.github/workflows/swift.yml

@@ -12,7 +12,7 @@ jobs:
   build:
     runs-on: macos-15
     steps:
-    - uses: actions/checkout@v4
+    - uses: actions/checkout@v5
     - name: Install swiftlint
       run: |
         brew update