Update actions/checkout action to v5 (#20)

Co-authored-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

Author: renovate[bot]

.github/workflows/ci.yml

@@ -19,7 +19,7 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@ee0669bd1cc54295c223e0bb666b733df41de1c5 # v2
+      - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5
       - name: Set up JDK
         uses: actions/setup-java@dded0888837ed1f317902acf8a20df0ad188d165 # v5
         with:
@@ -39,7 +39,7 @@ jobs:
     runs-on: ubuntu-latest
     needs: [build]
     steps:
-      - uses: actions/checkout@ee0669bd1cc54295c223e0bb666b733df41de1c5 # v2
+      - uses: actions/checkout@08c6903cd8c0fde910a37f88322edcfb5dd907a8 # v5
       - name: Set up JDK
         uses: actions/setup-java@dded0888837ed1f317902acf8a20df0ad188d165 # v5
         with: