Issue/revert paging3 migration

[khaykov]

Fixes #14860

Migration to Paging 3 is causing some issues with Post List. We need a bit more for a partial or full migration to Paging 3.

This PR removes the Paging 3 dependency and comments out the code that is using it, since it's behind the feature flag.

To test:

• Make sure that the app builds without any issue.
• Go to the post list and scroll down quickly
• Notice that post loading is performed correctly, the list remains visible and nothing crashes.

Regression Notes

1. Potential unintended areas of impact
   We are removing the offending library so should be none.

2. What I did to test those areas of impact (or what existing automated tests I relied on)

3. What automated tests I added (or what prevented me from doing so)

PR submission checklist:

• I have completed the Regression Notes.
• I have considered adding accessibility improvements for my changes.
• I have considered if this change warrants user-facing release notes and have added them to RELEASE-NOTES.txt if necessary.

[peril-wordpress-mobile]

You can trigger optional UI/connected tests for these changes by visiting CircleCI here.

[peril-wordpress-mobile]

You can test the changes on this Pull Request by downloading the APKs:

• Jetpack-pr-14949-build-111708.apk
• WordPress-pr-14949-build-111708.apk

[develric]

Hey @khaykov , was able to replicate the crash in a test site with more than 100 test draft post. Also confirm I didn't get the crash with the apk from this PR. Did some smoke testing and didn't encounter issues. We should be safe to go 👍 !