Update ci.yml

Author: kyleconroy

.github/workflows/ci.yml

@@ -12,5 +12,5 @@ jobs:
     - uses: actions/checkout@v3
     - uses: actions/setup-go@v4
       with:
-        go-version: '1.21.0-rc.2'
+        go-version: '1.21.0'
     - run: make