Update: Add golang v1.21 to build (#48)

Author: Eric Powers

.github/workflows/build-go.yaml

@@ -20,10 +20,11 @@ jobs:
       matrix:
         go:
           - "1.20"
+          - "1.21"
     steps:
       - uses: actions/checkout@v3
 
-      - uses: actions/setup-go@v3
+      - uses: actions/setup-go@v4
         with:
           go-version: ${{ matrix.go }}
           cache: true