Remove pull_request trigger from generate-bp workflow

This commit removes the `pull_request` trigger from the
`generate-bp.yml` workflow. This change was made to reduce
the amount of time and resources spent on building baseline
profiles, as it is only necessary to build them for pushes
on the `main` branch.

Author: cartland

.github/workflows/generate-bp.yml

@@ -1,10 +1,10 @@
 name: Generate Baseline Profiles
 
 on:
+  # We ONLY want to build baseline profiles for pushes on main.
+  # Do not trigger on "pull_request" because it takes too much time and resources.
   push:
     branches: [ main ]
-  pull_request:
-    branches: [ main ]
   workflow_dispatch:
 
 concurrency: