chore(security): Fix closed events for semgrep (#173)

CI has been failing for closed pull request events, fixing that by
removing the `closed` events as this already runs on pre-merge events

## Test plan

- CI 🟢 

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Author: shivasurya

.github/workflows/semgrep.yml

@@ -2,7 +2,7 @@ name: Semgrep - SAST Scan
 
 on:
   pull_request_target:
-    types: [ closed, edited, opened, synchronize, ready_for_review ]
+    types: [ edited, opened, synchronize, ready_for_review ]
 
 jobs:
   semgrep: