Add GitHub actions

Author: kyleconroy

.github/workflows/ci.yml

@@ -0,0 +1,15 @@
+name: build
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v3
+    - uses: actions/setup-go@v4
+      with:
+        go-version: '1.21.0'
+    - run: make