ci: remove caching step from CI workflow

.gitea/workflows/ci.yml

@@ -17,16 +17,6 @@ jobs:
         with:
           distribution: "temurin"
           java-version: "22"
-
-      - uses: actions/cache@v3
-        working-directory: ./backend
-        with:
-          path: |
-            ~/.gradle/caches
-            ~/.gradle/wrapper
-          key: ${{ runner.os }}-gradle-${{ hashFiles('**/*.gradle*', '**/gradle-wrapper.properties') }}
-          restore-keys: |
-            ${{ runner.os }}-gradle-
       - name: "Prepare Gradle"
         working-directory: ./backend
         run: gradle clean