Group all dependabot updates together in the same commit to avoid mer…

…ge conflicts.

Also change the interval from daily to weekly so there's only one update commit per triage rotation.

See https://docs.github.com/en/code-security/dependabot/dependabot-version-updates/configuration-options-for-the-dependabot.yml-file#configuration-options-for-the-dependabotyml-file for documentation on the configuration options.

RELNOTES=n/a
PiperOrigin-RevId: 640191662

.github/dependabot.yml

@@ -3,8 +3,18 @@ updates:
   - package-ecosystem: "maven"
     directory: "/"
     schedule:
-      interval: "daily"
+      interval: "weekly"
+    groups:
+      dependencies:
+        applies-to: version-updates
+        patterns:
+          - "*"
   - package-ecosystem: "github-actions"
     directory: "/"
     schedule:
-      interval: "daily"
+      interval: "weekly"
+    groups:
+      github-actions:
+        applies-to: version-updates
+        patterns:
+          - "*"