Replace mergify with action (#619)

.github/mergify.yml

@@ -1,25 +0,0 @@
-queue_rules:
-  - name: default
-    conditions:
-      - check-success=build
-      - check-success=lint
-      - check-success=test
-      - label=automerge
-      - base=master
-      - "#changes-requested-reviews-by=0"
-      - "#approved-reviews-by>=1"
-
-pull_request_rules:
-  - name: auto merge
-    conditions:
-      - check-success=build
-      - check-success=lint
-      - check-success=test
-      - label=automerge
-      - base=master
-      - "#changes-requested-reviews-by=0"
-      - "#approved-reviews-by>=1"
-    actions:
-      queue:
-        name: default
-        method: squash

.github/workflows/merge.yml

@@ -0,0 +1,17 @@
+name: PR
+
+on:
+  pull_request:
+    types: [labeled]
+
+jobs:
+  auto-merge:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: jacogr/action-merge@master
+        with:
+          checks: build,lint,test
+          labels: automerge
+          strategy: squash
+          token: ${{ secrets.GH_PAT_BOT }}