Update actions/cache action to v6

Author: renovate[bot]

.github/workflows/mvn.yml

@@ -20,7 +20,7 @@ jobs:
         with:
           distribution: 'temurin'
           java-version: ${{ matrix.java }}
-      - uses: actions/cache@v3
+      - uses: actions/cache@v6
         with:
           path: ~/.m2/repository
           key: ${{ runner.os }}-jdk-${{ matrix.java }}-maven-${{ hashFiles('**/pom.xml') }}

.github/workflows/reports.yml

@@ -16,7 +16,7 @@ jobs:
         uses: actions/setup-java@v3
         with:
           java-version: 11
-      - uses: actions/cache@v3
+      - uses: actions/cache@v6
         with:
           path: ~/.m2/repository
           key: maven-${{ hashFiles('**/pom.xml') }}