fix: Multiple fixes

[filipecabaco]

What kind of change does this PR introduce?

• Remove +sbwt flag change until we handle a syn issue found in load testing
• Change worker.js implementation to receive the heartbeat time from configuration
• Add migration to create index for external_id on extensions - https://github.com/supabase/realtime/issues/1140
• Reduce test flakiness

[vercel[bot]]

The latest updates on your projects. Learn more about Vercel for Git ↗︎

1 Skipped Deployment

| Name | Status | Preview | Comments | Updated (UTC) | | :--- | :----- | :------ | :------- | :------ | | **realtime-demo** | ⬜️ Ignored ([Inspect](https://vercel.com/supabase/realtime-demo/6Pccu2BxVg2ENsLp7V7rSExXnfyw)) | [Visit Preview](https://realtime-demo-git-fix-multiple-fixes-supabase.vercel.app) | | Sep 2, 2024 6:06pm |

[kiwicopple]

:tada: This PR is included in version 2.30.34 :tada:

The release is available on GitHub release

Your semantic-release bot :package::rocket: