Update Live migration docs

[VineethReddy02]

Description

Update live migration docs with fixes and better explanation on database switchover.

Links

Fixes #[insert issue link, if any]

Writing help

For information about style and word usage, see the style guide

Review checklists

Reviewers: use this section to ensure you have checked everything before approving this PR:

Subject matter expert (SME) review checklist

• [ ] Is the content technically accurate?
• [ ] Is the content complete?
• [ ] Is the content presented in a logical order?
• [ ] Does the content use appropriate names for features and products?
• [ ] Does the content provide relevant links to further information?

Documentation team review checklist

• [ ] Is the content free from typos?
• [ ] Does the content use plain English?
• [ ] Does the content contain clear sections for concepts, tasks, and references?
• [ ] Have any images been uploaded to the correct location, and are resolvable?
• [ ] If the page index was updated, are redirects required and have they been implemented?
• [ ] Have you checked the built version of this content?

[github-actions[bot]]

Allow 10 minutes from last push for the staging site to build. If the link doesn't work, try using incognito mode instead. For internal reviewers, check web-documentation repo actions for staging build status. Link to build for this PR: http://docs-dev.timescale.com/docs-vineeth-nits-live-migration

[billy-the-fish]

@VineethReddy02, would you like me to work on the comments made for this issue or shall we close it?

[Harkishen-Singh]

It seems like the PR has become outdated, and it might be best to close it and create a new one. There have been notable changes in the live migration documentation since this PR was initially submitted.