Move LocalPodspecPatch to dedicated file

[cipolleschi]

Summary:
This diff moves the monkeypatch LocalPodspecPatch to a dedicated ruby file.
It also adds test for that

Changelog

[iOS][Changed] - Move LocalPodspecPatch to dedicated file

Reviewed By: cortinico

Differential Revision: D37069361

[facebook-github-bot]

This pull request was exported from Phabricator. Differential Revision: D37069361

[analysis-bot]

Platform	Engine	Arch	Size (bytes)	Diff
android	hermes	arm64-v8a	7,824,361	+0
android	hermes	armeabi-v7a	7,211,577	+0
android	hermes	x86	8,135,005	+0
android	hermes	x86_64	8,115,150	+0
android	jsc	arm64-v8a	9,691,266	+0
android	jsc	armeabi-v7a	8,447,374	+0
android	jsc	x86	9,642,663	+0
android	jsc	x86_64	10,239,837	+0

Base commit: 5854b11
Branch: main

[analysis-bot]

Platform	Engine	Arch	Size (bytes)	Diff
ios	-	universal	n/a	--

Base commit: 71da212
Branch: main

[react-native-bot]

This pull request was successfully merged by @cipolleschi in 8fe2b59.

^{When will my fix make it into a release? | Upcoming Releases}