[GitHub] Update pull request template with supported triggers

Author: shahmishal

.github/PULL_REQUEST_TEMPLATE.md

@@ -21,17 +21,27 @@ The swift-ci is triggered by writing a comment on this PR addressed to the GitHu
         Platform     | Comment
         ------------ | -------------
         All supported platforms     | @swift-ci Please smoke test
+        All supported platforms     | @swift-ci Please smoke test and merge
         OS X platform               | @swift-ci Please smoke test OS X platform
         Linux platform              | @swift-ci Please smoke test Linux platform
 
- **Validation Testing**
+**Validation Testing**
 
         Platform     | Comment
         ------------ | -------------
         All supported platforms     | @swift-ci Please test
+        All supported platforms     | @swift-ci Please test and merge
         OS X platform               | @swift-ci Please test OS X platform
+        OS X platform               | @swift-ci Please benchmark
         Linux platform              | @swift-ci Please test Linux platform
 
+
+**Lint Testing**
+
+        Language     | Comment
+        ------------ | -------------
+        Python       | @swift-ci Please Python lint
+
 Note: Only members of the Apple organization can trigger swift-ci.
 </details>
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