fix core install path

Author: kkoreilly

.github/workflows/go.yml

@@ -19,7 +19,7 @@ jobs:
         go-version: '1.23.4'
 
     - name: Set up Core
-      run: go install cogentcore.org/core/cmd/core@main && core setup
+      run: go install cogentcore.org/core@main && core setup
 
     - name: Build
       run: go build -v ./...