test: add test case for issue 53702

test: add test case for issue 53702

The issue is expected to be fixed when Unified IR is enabled by default,
so adding a test to make sure thing works correctly.

Updates #53702

Change-Id: Id9d7d7ca4506103df0d10785ed5ee170d69988ba
Reviewed-on: https://go-review.googlesource.com/c/go/+/423434
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com>
Auto-Submit: Cuong Manh Le <cuong.manhle.vn@gmail.com>