add mergify (#143)

Author: Lazar955

.mergify.yml

@@ -0,0 +1,25 @@
+queue_rules:
+  - name: default
+    queue_conditions:
+      - "#approved-reviews-by>1"
+      - base=main
+      - label=A:automerge
+    merge_conditions:
+      - "#approved-reviews-by>1"
+    commit_message_template: |
+      {{ title }} (#{{ number }})
+      {{ body }}
+    merge_method: squash
+pull_request_rules:
+  - name: backport changes to release/v0.16.x branch
+    conditions:
+      - base=main
+      - label=backport-to-release/v0.16.x
+    actions:
+      backport:
+        branches:
+          - release/v0.16.x
+  - name: automerge to main with label automerge and branch protection passing
+    conditions: []
+    actions:
+      queue: