Add Gradle dependency updates to Dependabot configuration

Author: jacopoc

.github/README-CI-CD.md

@@ -45,6 +45,7 @@ Read **only from `trunk`**.
 Updates:
 - GitHub Actions
 - Docker base images
+- Gradle dependencies
 - NPM (`themes/common-theme/.../js`)
 
 Each ecosystem includes:
@@ -54,6 +55,7 @@ Each ecosystem includes:
 ## New release branch checklist
 
 Before creating a new release branch from `trunk`, update `dependabot.yml` (on `trunk`) by adding a `target-branch` entry for:
+- gradle
 - npm
 - github-actions
 - docker

.github/dependabot.yml

@@ -20,6 +20,33 @@
 
 version: 2
 updates:
+  - package-ecosystem: "gradle"
+    directory: "/"
+    schedule:
+      interval: "daily"
+    #groups:
+    #  all-dependencies:
+    #    patterns:
+    #      - "*"
+    ignore:
+      - dependency-name: "*"
+        update-types:
+          - "version-update:semver-major"
+
+  - package-ecosystem: "gradle"
+    directory: "/"
+    target-branch: "release24.09"
+    schedule:
+      interval: "daily"
+    #groups:
+    #  all-dependencies:
+    #    patterns:
+    #      - "*"
+    ignore:
+      - dependency-name: "*"
+        update-types:
+          - "version-update:semver-major"
+
   - package-ecosystem: "npm"
     directory: "themes/common-theme/webapp/common-theme/js"
     schedule: