Bump up actions/cache to v4 (#735)

.github/actions/build/action.yml

@@ -39,7 +39,7 @@ runs:
         sed -i "/<\/sourceDirectories>/i <sourceDirectory>scenarios\/""${{ inputs.test_case }}""<\/sourceDirectory>" test/plugin/pom.xml
         echo "::endgroup::"
     - name: Cache local Maven repository
-      uses: actions/cache@v2
+      uses: actions/cache@v4
       with:
         path: ~/.m2/repository
         key: ${{ runner.os }}-maven-agent-test-${{ hashFiles('**/pom.xml') }}

.github/actions/run/action.yml

@@ -42,7 +42,7 @@ runs:
           docker load -i test-containers/skywalking-agent-test-tomcat-1.0.0.tgz
         fi
     - name: Cache local Maven repository
-      uses: actions/cache@v2
+      uses: actions/cache@v4
       with:
         path: ~/.m2/repository
         key: ${{ runner.os }}-maven-agent-test-run-${{ hashFiles('**/pom.xml') }}

.github/workflows/ci.yaml

@@ -57,7 +57,7 @@ jobs:
         with:
           submodules: true
       - name: Cache local Maven repository
-        uses: actions/cache@v2
+        uses: actions/cache@v4
         with:
           path: ~/.m2/repository
           key: ${{ runner.os }}-maven-ci-${{ hashFiles('**/pom.xml') }}

.github/workflows/publish-docker.yaml

@@ -36,7 +36,7 @@ jobs:
         with:
           submodules: true
       - name: Cache local Maven repository
-        uses: actions/cache@v2
+        uses: actions/cache@v4
         with:
           path: ~/.m2/repository
           key: ${{ runner.os }}-maven-publish-docker-${{ hashFiles('**/pom.xml') }}