Create pull.yml

Author: MaxDesiatov

.github/pull.yml

@@ -0,0 +1,15 @@
+version: "1"
+rules:
+  - base: swiftwasm
+    upstream: swift/master
+    mergeMethod: merge
+  - base: swift/master
+    upstream: apple:swift/master
+    mergeMethod: hardreset
+  - base: swift/release/5.3
+    upstream: apple:swift/release/5.3
+    mergeMethod: hardreset
+  - base: swiftwasm-release/5.3
+    upstream: swift/release/5.3
+    mergeMethod: merge
+label: ":arrow_heading_down: Upstream Tracking"