add repo checkout action

Author: neel1996

.github/workflows/main.yml

@@ -7,6 +7,15 @@ jobs:
     name: Gitconvex test
     runs-on: ubuntu-latest
     steps:
+      - name: Set up Go 1.x
+        uses: actions/setup-go@v2
+        with:
+          go-version: ^1.16
+        id: go
+      
+      - name: Check out code into the Go module directory
+        uses: actions/checkout@v2
+
       - name: Run Go Test
         run: |
           go test -v ./...