React compatibility: Remove react-test-renderer

[coder-karen]

In React 19, react-test-renderer will be deprecated (reference). While it will not be removed in React 19 and only log a deprecation warning, we don't specifically appear to be using it within the monorepo except for one case, though this should be tested and confirmed before removing it.

In that one case, we specifically use react-test-renderer/shallow, and that will be removed in React 19 (reference), to prefer installing the package directly.

Parent issue: #37951