Delete gradle wrapper workflow

Dependabot now does this

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

@@ -1,20 +0,0 @@
-name: Update Gradle Wrapper
-
-on:
-  schedule:
-    - cron: "0 0 * * *"
-
-permissions:
-  contents: write
-  pull-requests: write
-
-jobs:
-  update-gradle-wrapper:
-    runs-on: ubuntu-latest
-
-    steps:
-      - uses: actions/checkout@v6
-        with:
-          persist-credentials: false
-      - name: Update Gradle Wrapper
-        uses: gradle-update/update-gradle-wrapper-action@v2