fix: on iOS not getting 304 from `If-None-Match` request

[huzhanbo1996]

Summary:

In #44483 If-None-Match request failed to get a 304 after a 200 response. This is caused by NSRequest's cachePolicy which prevents sending a request to server to check 304 state and return directly a 200 response.

Changelog:

[IOS] [FIXED] - fix: on iOS not getting 304 from If-None-Match request

Test Plan:

repeat request given in #44483

[analysis-bot]

Platform	Engine	Arch	Size (bytes)	Diff
android	hermes	arm64-v8a	19,691,034	-609,854
android	hermes	armeabi-v7a	n/a	--
android	hermes	x86	n/a	--
android	hermes	x86_64	n/a	--
android	jsc	arm64-v8a	22,896,039	-601,461
android	jsc	armeabi-v7a	n/a	--
android	jsc	x86	n/a	--
android	jsc	x86_64	n/a	--

Base commit: 3c6762a5f8860c04043e2217a00572384c8d423a Branch: main

[facebook-github-bot]

@dmytrorykun has imported this pull request. If you are a Meta employee, you can view this diff on Phabricator.

[facebook-github-bot]

@dmytrorykun merged this pull request in facebook/react-native@b8ab0fe703f1a0aca796bc15641d029a2036105f.

[github-actions[bot]]

This pull request was successfully merged by @huzhanbo1996 in b8ab0fe703f1a0aca796bc15641d029a2036105f.

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