Fix Cache checks in build_hermes_macos (#45127)

Summary:
The cache checks in GHA were performed against bool values, while the actual values are strings.
So the checks were always failing and all the steps were executed, even when not necessary.

The reason why it was failing is because, with this setup, when a cache is hit, some steps were skipped in previous jobs, making following jobs trying to execute code on not-existing files.

## Changelog:
[Internal] - Fix cache for build_hermes_macos

Pull Request resolved: https://github.com/facebook/react-native/pull/45127

Test Plan: GHA are green again

Reviewed By: blakef

Differential Revision: D58947838

Pulled By: cipolleschi

fbshipit-source-id: 8dba216e72a3034fd4c1484418d37bfb78cf314d