dependabot: enable update grouping

This should group updates into a single PR. Hopefully, that simplfies
updates.

Updates that do _actually_ require code changes, will need a separate PR
anyway, after which dependabot can be asked to rebase/recreate.

Suggested-by: Patrick Roy <[email protected]>
Suggested-by: Stefano Garzarella <[email protected]>
Signed-off-by: Erik Schilling <[email protected]>

Author: Erik Schilling

.github/dependabot.yml

@@ -4,10 +4,13 @@ updates:
   directory: "/"
   schedule:
     interval: weekly
-  open-pull-requests-limit: 3
   allow:
   - dependency-type: direct
   - dependency-type: indirect
+  groups:
+      vhost-device:
+        patterns:
+          - "*"
 - package-ecosystem: gitsubmodule
   directory: "/"
   schedule: