ci: update the setup-go version

Version 2 wants to use the old URL so that also fails to run. The latest is
version 6 so let's update to that and at the same time update to the same Go
version that we want to download in the build script.

Author: carlosmn

.github/workflows/test.yml

@@ -12,9 +12,9 @@ jobs:
     runs-on: ${{ matrix.os }}
     steps:
       - name: Set up Go
-        uses: actions/setup-go@v2
+        uses: actions/setup-go@v6
         with:
-          go-version: '1.17'
+          go-version: '1.21.3'
 
       - name: Check out code
         uses: actions/checkout@v2