Fix race condition in context cancellation check

Use select statement instead of ctx.Err() check to avoid race condition
when checking for context cancellation in the goroutine error handler.

This follows Go best practices for context handling.

Addresses review comment from @yrobla.

Author: jhrozek

test/integration/vmcp/helpers/vmcp_server.go

@@ -188,9 +188,13 @@ func NewVMCPServer(
 	// Start server automatically
 	// Use the passed-in context to ensure proper cancellation propagation
 	go func() {
-		if err := vmcpServer.Start(ctx); err != nil && ctx.Err() == nil {
-			// Only report error if context wasn't cancelled
-			tb.Errorf("vMCP server error: %v", err)
+		if err := vmcpServer.Start(ctx); err != nil {
+			select {
+			case <-ctx.Done():
+				// Context cancelled, ignore error
+			default:
+				tb.Errorf("vMCP server error: %v", err)
+			}
 		}
 	}()