feat: removed backend pipeline step for caching m2

.gitea/workflows/backend-ci.yml

@@ -26,13 +26,6 @@ jobs:
         distribution: 'temurin'
         cache: 'maven'
         
-    - name: Cache Maven packages
-      uses: actions/cache@v3
-      with:
-        path: ~/.m2
-        key: ${{ runner.os }}-m2-${{ hashFiles('**/pom.xml') }}
-        restore-keys: ${{ runner.os }}-m2
-        
     - name: Run Maven tests
       working-directory: ./backend
       run: mvn test