Fix Receive PR workflow & rm unit-test pr trigger

.github/workflows/pr-receive.yml

@@ -12,9 +12,6 @@ jobs:
     steps:
       - uses: actions/checkout@v2
 
-      - name: Build
-        run: /bin/bash ./build.sh
-
       - name: Save PR number
         run: |
           mkdir -p ./pr

.github/workflows/unit-test.yml

@@ -3,8 +3,6 @@ name: UnitTest
 on:
   push:
     branches: [main]
-  pull_request:
-    branches: [main]
 
 env:
   YAO_DEV: ${{ github.WORKSPACE }}