Auth deprecated methods removal

[jonsimantov]

Description

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

Remove methods that were deprecated in the 11.0.0 release last year.

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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.

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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.

[github-actions]

❌  Integration test FAILED

Requested by @jonsimantov on commit edb9720
Last updated: Thu May 2 19:28 PDT 2024
View integration test log & download artifacts

Failures	Configs
missing_log	[TEST] [ERROR] [Windows] [x64] [openssl]
firestore	[TEST] [FLAKINESS] [Android] [1/3 os: ubuntu] [1/2 android_device: android_target] (1 failed tests)   CRASH/TIMEOUT

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

[jonsimantov]

Another sanity check to try, run the reference doc generation, and make sure that looks good.

Makes sense - running packaging workflow to generate docs from.

[jonsimantov]

Another sanity check to try, run the reference doc generation, and make sure that looks good.

Confirmed that docs generation looks good, merging this.