ci: fetch submodules for github workflow

Author: losh11

.github/workflows/go.yml

@@ -19,6 +19,8 @@ jobs:
 
       - name: Check out source
         uses: actions/checkout@v2
+        with:
+          submodules: recursive
 
       - name: Build
         run: make build
@@ -34,6 +36,8 @@ jobs:
 
       - name: Check out source
         uses: actions/checkout@v2
+        with:
+          submodules: recursive
 
       - name: Test
         run: make unit-cover
@@ -82,6 +86,8 @@ jobs:
 
       - name: Check out source
         uses: actions/checkout@v2
+        with:
+          submodules: recursive
 
       - name: Test
         run: make unit-race