Enable grouped version updates (#1878)

Prevents several PRs to be created. This can be improved to group dependencies (test libs, dev libs ...) in case a lib might block others.

.github/dependabot.yml

@@ -9,3 +9,8 @@ updates:
     directory: "/" # Location of package manifests
     schedule:
       interval: "weekly"
+    groups:
+       # Grouped version updates configuration
+       all-dependencies:
+          patterns:
+            - "*"