Fix E2E Tests by configuring git (#53357)

Summary:
E2E tests on iOS started failing yesterday because of some permission model that has changed in Github.

When creating a new app from the template, we initialize a git repository. The initialization started failing with the error:
```
debug Could not create an empty Git repository, error: , Error: Command failed with exit code 128: git commit -m Initial commit

Author identity unknown

*** Please tell me who you are.

Run

  git config --global user.email "[email protected]"
  git config --global user.name "Your Name"

to set your account's default identity.
Omit --global to set the identity only in this repository.

fatal: unable to auto-detect email address (got 'runner@sat12-jr314_3f88162a-0f3d-4d26-80dc-58f431cca4c6-9A2607311B51.(none)')
```

This change fixes it by setting a default identity for git in the CI jobs that requires it.

## Changelog:
[Internal] -

Pull Request resolved: https://github.com/facebook/react-native/pull/53357

Test Plan: GHA

Reviewed By: cortinico

Differential Revision: D80612345

Pulled By: cipolleschi

fbshipit-source-id: 85816057d910ed3619c5f683fdad724c3df8046b