reconfigure mergify

.mergify.yml

@@ -1,7 +1,18 @@
+---
 pull_request_rules:
   - name: Automatic merge on approval
     conditions:
       - "#approved-reviews-by>=1"
     actions:
       merge:
         method: merge
+  - name: automatic merge for Dependabot pull requests
+
+    conditions:
+      - author~=^dependabot(|-preview)\[bot\]$
+      - check-success=CI - test and coverage / test (pull_request)
+      - title~=^Bump [^\s]+ from ([\d]+)\..+ to \1\.
+
+    actions:
+      merge:
+        method: merge