Run test on PR (#135)

Author: fjchen7

.github/workflows/test.yml

@@ -1,17 +1,15 @@
-on: push
 name: Test
+on:
+  pull_request:
+    types: [ opened, reopened, synchronize, edited ]
 jobs:
   test:
-    strategy:
-      matrix:
-        go-version: [ 1.14.x, 1.15.x ]
-        os: [ ubuntu-latest, macos-latest, windows-latest ]
-    runs-on: ${{ matrix.os }}
+    runs-on: ubuntu-latest
     steps:
       - name: Install Go
         uses: actions/setup-go@v2
         with:
-          go-version: ${{ matrix.go-version }}
+          go-version: '1.17'
       - name: Checkout code
         uses: actions/checkout@v2
       - name: Test