Change Firestore external ref to one with patch.exe bugfix

[jonsimantov]

Description

Provide details of the change, and generalize the change in the PR title above.

In the Firestore iOS SDK, the usage of patch.exe crashes on Windows due to CRLF issues. This is fixed in that repo by firebase/firebase-ios-sdk#9941; use that commit in the C++ SDK, since it was not included in the 9.2.0 release. (The commit was branched off of the CocoaPods-9.2.0 tag.)

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Testing

Describe how you've tested these changes. Link any manually triggered Integration tests or CPP binary SDK Packaging Github Action workflows, if applicable.

Running C++ Packaging workflow.

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Type of Change

Place an x the applicable box:

• Bug fix. Add the issue # below if applicable.
• New feature. A non-breaking change which adds functionality.
• Other, such as a build process or documentation change.

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Notes

• Bug fixes and feature changes require an update to the Release Notes section of release_build_files/readme.md.
• Read the contribution guidelines CONTRIBUTING.md.
• Changes to the public API require an internal API review. If you'd like to help us make Firebase APIs better, please propose your change in a feature request so that we can discuss it together.

[dconeybe]

For posterity and cross-referencing, this PR effectively patches in firebase/firebase-ios-sdk#9941 to the cmake builds here in the cpp sdk.

[github-actions]

Integration test with FLAKINESS (succeeded after retry)

Requested by @DellaBitta on commit 33d2162
Last updated: Fri Jun 24 07:06 PDT 2022
View integration test log & download artifacts

Failures	Configs
firestore	[TEST] [FLAKINESS] [Android] [1/3 os: windows] [1/2 android_device: android_target] (1 failed tests)   CRASH/TIMEOUT

Add flaky tests to go/fpl-cpp-flake-tracker