Add github-actions upgrade to Dependabot config

* Refactor `dependabot.yml` for better readability

.github/dependabot.yml

@@ -1,23 +1,39 @@
 version: 2
 updates:
-  - package-ecosystem: "gradle"
-    directory: "/"
+  - package-ecosystem: gradle
+    directory: /
     schedule:
-      interval: "weekly"
-      day: "sunday"
+      interval: weekly
+      day: sunday
     ignore:
-      - dependency-name: "*"
-        update-types: ["version-update:semver-major", "version-update:semver-minor"]
+      - dependency-name: '*'
+        update-types:
+          - version-update:semver-major
+          - version-update:semver-minor
     open-pull-requests-limit: 10
-    labels: ["type: dependency-upgrade"]
+    labels:
+      - 'type: dependency-upgrade'
     groups:
       development-dependencies:
-        update-types: ["patch"]
+        update-types:
+          - patch
         patterns:
-          - "com.gradle.enterprise"
-          - "com.github.spotbugs"
-          - "io.spring.*"
-          - "org.ajoberstar.grgit"
-          - "com.icegreen:greenmail"
-          - "org.mock-server*"
-          - "org.apache.curator*"
+          - com.gradle.enterprise
+          - com.github.spotbugs
+          - io.spring.*
+          - org.ajoberstar.grgit
+          - com.icegreen:greenmail
+          - org.mock-server*
+          - org.apache.curator*
+
+  - package-ecosystem: github-actions
+    directory: /
+    schedule:
+      interval: weekly
+      day: saturday
+    labels:
+      - 'type: task'
+    groups:
+      development-dependencies:
+        patterns:
+          - '*'