fix(test): fix RNTester iOS unit and integration tests (#53848)

Summary:
This PR fixes problems with unit & integration tests in the iOS RNTester project, related to: compilation errors, JS problems, missing mocks & outdated baselines.

## Changelog:

[Internal] - Re-enabled iOS unit & integration tests, Ruby tests on CI, stripped obsolete build part before running tests, renamed uploaded xcresult artifacts

Pull Request resolved: https://github.com/facebook/react-native/pull/53848

Test Plan:
1. iOS tests pass:

- When run from dedicated xcschemes:

<img width="596" height="388" alt="image" src="https://github.com/user-attachments/assets/9f3a038b-f12e-4b12-ab95-93d55eb60d63" />

<img width="611" height="381" alt="image" src="https://github.com/user-attachments/assets/27ff3a6f-57da-4842-a96c-db569e417dc3" />

- When run from the RNTester scheme (command + U):

<img width="754" height="384" alt="image" src="https://github.com/user-attachments/assets/0b4a6e70-56da-40c1-b019-b1e87d8df591" />

2. Ruby scripting tests pass:

<img width="655" height="349" alt="image" src="https://github.com/user-attachments/assets/a6a41d16-2744-44c9-bf87-e4a06f228cfb" />

3. CI - green
4. xcresult artifacts are uploaded
<img width="1370" height="478" alt="image" src="https://github.com/user-attachments/assets/1bd0638d-f215-48f7-b798-fadb8799c5f7" />

Reviewed By: huntie

Differential Revision: D88733170

Pulled By: cipolleschi

fbshipit-source-id: e14c69bede1db34461926726bc796804b365a7a9