Pin Xcodeproj to < 1.26.0 (#47237)

Summary:
Pull Request resolved: https://github.com/facebook/react-native/pull/47237

The Xcodeproj gem has been released yesterday to version 1.26.0 and it broke the CI pipeline of react native.

This should fix the issue

[Internal] - Pin Xcodeproj gem to 1.26.0

Reviewed By: blakef

Differential Revision: D65057797

fbshipit-source-id: f4035a1d3c75dd4140eb1646ab2aa0ccb08fb16b