Revert "Fix @Test annotation to make Kotlin 2.2 happy."

This reverts commit 28b943f0.

Reason for revert: b/438184175 - the '=' notation breaks presubmits when used with `assertThrows` as a top-level call, because it is not a void function

Bug: 427745324
Change-Id: I42e0526e47674b6b249a4fbb558fc4c742e34b90