Update github CI trigger events (#192)

* Avoid duplicated github actions checks for pull-request/push events.
* Only trigger CI on a subset of pull request events: opened, reopened and synchronized.

Signed-off-by: Ivan Santiago Paunovic <ivanpauno@ekumenlabs.com>

Author: ivanpauno

.github/workflows/build_and_test.yml

@@ -1,6 +1,13 @@
 name: CI
 
-on: [push, pull_request]
+on:
+  push:
+    branches: [main]
+  pull_request:
+    branches: [main]
+    types: [opened, reopened, synchronize]
+
+
 
 jobs:
   build_and_test: