Fix workflow

.github/workflows/go.yml

@@ -5,7 +5,7 @@ jobs:
     name: Test
     strategy:
       matrix:
-        os: [ "ubuntu-latest", "macos-latest" ]
+        os: [ "ubuntu-latest", "macos-latest", "windows-latest" ]
         go-version: [ "1.13", "1.14", "1.15" ]
     runs-on: ${{ matrix.os }}
     steps:
@@ -15,16 +15,6 @@ jobs:
         go-version: ${{ matrix.go-version }}
     - name: checkout
       uses: actions/checkout@v2
-    - uses: actions/cache@v2
-      with:
-        path: |
-          ~/go/pkg/mod
-          ~/.cache/go-build
-          ~/Library/Caches/go-build
-          '%LocalAppData%\go-build'
-        key: ${{ matrix.os }}-go-${{ hashFiles('**/go.sum') }}
-        restore-keys: |
-          ${{ matrix.os }}-go-
     - name: simple test
       run: go test -v ./ -count=1
     - name: test with GC pressure
@@ -32,6 +22,7 @@ jobs:
       env:
         GOGC: 1
     - name: test with race detector
+      if: ${{ matrix.os == 'macos-latest' }}
       run: go test -v -race ./ -count=1
   coverage:
     name: Coverage