Revert Dedicated Sync Endpoints

[kraftbj]

• Revert Jetpack Sync: Introduce custom endpoint for spawning Sync requests #24344

Changes proposed in this Pull Request:

• This reverts removes problematic code while we investigate an incident on the Atomic platform.

Jetpack product discussion

p9o2xV-26K-p2

Does this pull request change what data or activity we track or use?

No.

Testing instructions:

• Still investigating how to duplicate the issues thrown.

[github-actions]

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