ci(mergify): upgrade configuration to current format

Author: mergify[bot]

.mergify.yml

@@ -7,18 +7,20 @@ queue_rules:
       - and: &CheckRuns
           - check-success=test
       - schedule=Mon-Fri 09:00-17:30[Europe/Paris]
-    speculative_checks: 5
-
   - name: lowprio
-    allow_inplace_checks: true
-    conditions:
+    queue_conditions:
+      - and: *CheckRuns
+      - author=dependabot[bot]
+      - label!=work-in-progress
+      - label!=manual merge
+    merge_conditions:
       - and: *CheckRuns
       - schedule=Mon-Fri 09:00-17:00[Europe/Paris]
+    allow_inplace_checks: true
     batch_size: 7
     batch_max_wait_time: 5min
     queue_branch_merge_method: fast-forward
-    disallow_checks_interruption_from_queues:
-      - default
+    merge_method: merge
 
 pull_request_rules:
   - name: automatic merge
@@ -34,17 +36,6 @@ pull_request_rules:
       queue:
         name: default
 
-  - name: automatic merge from dependabot
-    conditions:
-      - and: *CheckRuns
-      - author=dependabot[bot]
-      - label!=work-in-progress
-      - label!=manual merge
-    actions:
-      queue:
-        name: lowprio
-        method: merge
-
   - name: request review
     conditions:
       - -author=dependabot[bot]
@@ -59,3 +50,6 @@ pull_request_rules:
       request_reviews:
         teams:
           - devs
+
+merge_queue:
+  max_parallel_checks: 5