Fix Go test function name to use ask_user folder and remove unused askuser folder

Co-authored-by: patniko <26906478+patniko@users.noreply.github.com>

Author: Copilot

go/e2e/ask_user_test.go

@@ -9,7 +9,7 @@ import (
 	"github.com/github/copilot-sdk/go/e2e/testharness"
 )
 
-func TestAskUser(t *testing.T) {
+func TestAsk_User(t *testing.T) {
 	ctx := testharness.NewTestContext(t)
 	client := ctx.NewClient()
 	t.Cleanup(func() { client.ForceStop() })