Configure dependabot for Gradle

Author: purejava

.github/dependabot.yml

@@ -1,28 +1,12 @@
 version: 2
 updates:
-  - package-ecosystem: "maven"
+  - package-ecosystem: "gradle"
     directory: "/"
     schedule:
       interval: "weekly"
       day: "saturday"
       time: "06:00"
       timezone: "Etc/UTC"
-    groups:
-      java-test-dependencies:
-        patterns:
-          - "org.junit.jupiter:*"
-      maven-build-plugins:
-        patterns:
-          - "org.apache.maven.plugins:*"
-          - "org.sonatype.plugins:*"
-      java-production-dependencies:
-        patterns:
-          - "*"
-        exclude-patterns:
-          - "org.openjfx:*"
-          - "org.apache.maven.plugins:*"
-          - "org.junit.jupiter:*"
-          - "org.sonatype.plugins:*"
 
   - package-ecosystem: "github-actions"
     directory: "/" # even for `.github/workflows`