Add gradle wrapper update workflow

.github/workflows/build.yml

@@ -1,5 +1,5 @@
-name: Java CI with Gradle
-on: [ pull_request, push ]
+name: Build
+on: [ pull_request, push, workflow_dispatch ]
 
 jobs:
   build:

.github/workflows/update-gradle-wrapper.yml

@@ -0,0 +1,14 @@
+name: Update Gradle Wrapper
+on:
+  workflow_dispatch:
+  schedule:
+    - cron: "0 0 * * 0"
+
+jobs:
+  update-gradle-wrapper:
+    runs-on: ubuntu-24.04
+    steps:
+      - name: Checkout Repository
+        uses: actions/checkout@v4
+      - name: Update Gradle Wrapper
+        uses: gradle-update/update-gradle-wrapper-action@v1