disable pr workflow runs

when this workflow is on the main branch, it'll be possible to start workflows manually, so we'll use that to test prs

.github/workflows/build-coop.yaml

@@ -1,17 +1,13 @@
 name: Build coop
 
 on:
-    push:
-        branches:
-            - dev
-    pull_request:
-        branches:
-            - "**"
     workflow_dispatch:
+    push:
+        branches: [ dev ]
 
 jobs:
     build-ubuntu:
-        if: ${{ contains(github.event.head_commit.message, '[build]') || github.event_name == 'workflow_dispatch' }}
+        if: ${{ github.event_name == 'workflow_dispatch' || contains(github.event.head_commit.message, '[build]') }}
         runs-on: ubuntu-latest
         steps:
             - name: Checkout repository
@@ -31,7 +27,7 @@ jobs:
                 name: sm64coopdx-ubuntu
                 path: ./build/us_pc/sm64coopdx
     build-windows:
-        if: ${{ contains(github.event.head_commit.message, '[build]') || github.event_name == 'workflow_dispatch' }}
+        if: ${{ github.event_name == 'workflow_dispatch' || contains(github.event.head_commit.message, '[build]') }}
         runs-on: windows-latest
         defaults:
             run: