Update actions to use Go1.16

Author: jszwec

.github/workflows/go.yml

@@ -11,7 +11,7 @@ jobs:
   test:
     strategy:
       matrix:
-        go-version: [1.14, 1.15]
+        go-version: [1.15, 1.16]
         os: [ubuntu-latest, macos-latest, windows-latest]
 
     runs-on: ${{ matrix.os }}