Update static-analysis.yml (#3480)

### Description

- Updates slither static analysis to run on main for use with github
code scanning

.github/workflows/static-analysis.yml

@@ -1,12 +1,17 @@
 name: static-analysis
 
 on:
-  # Triggers the workflow on pull request against main
-  pull_request:
+  push:
+  # Triggers the workflow on push to main
     branches: [main]
     paths:
       - 'solidity/**'
       - '.github/workflows/static-analysis.yml'
+  # Triggers the workflow on pull request
+  pull_request:
+    paths:
+      - 'solidity/**'
+      - '.github/workflows/static-analysis.yml'
 
 jobs:
   slither: