Fix typo in workflow

.github/workflows/main.yml

@@ -21,10 +21,10 @@ jobs:
         id: get_version
         uses: battila7/get-version-action@v2.0.0
 
-      - name: Setup Golang 1.15
+      - name: Setup Golang 1.13
         uses: actions/setup-go@v1
         with:
-          go-version: 1.15
+          go-version: 1.13
       
       - name: Install go-bindata and build migrations
         run: |