Bump GitHub Actions up

Author: pomadchin

.github/workflows/ci.yaml

@@ -6,13 +6,13 @@ jobs:
   build-and-test:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v2
+      - uses: actions/checkout@v4
       - name: Set up JDK 1.8
-        uses: actions/setup-java@v2
+        uses: actions/setup-java@v4
         with:
           distribution: 'adopt'
           java-version: '8'
-      - uses: actions/cache@v2
+      - uses: actions/cache@v4
         with:
           path: ~/.m2/repository
           key: ${{ runner.os }}-maven-${{ hashFiles('**/pom.xml') }}