Fix #632: Move PromotedStoryListAdapter to BindableAdater

[masclot]

Fix #632: Move PromotedStoryListAdapter to BindableAdater

This change reverts partially #4951, which in turn reverted #4874 due to a bug.
It is a partial revert because the bug was fixed independently in the previous PR #4965.

I added RecentlyPlayedViewModel.kt to the list of classes not needing tests, as is usual for ViewModels. This was also part of the original PR.

current	new

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If your PR includes UI-related changes, then:

• Add screenshots for portrait/landscape for both a tablet & phone of the before & after UI changes
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[adhiamboperes]

Thanks @masclot! This PR LGTM.

I just had one minor comment and also please add the landscape screenshots before merge.

[oppiabot]

Hi @masclot, this PR is ready to be merged. Please address any remaining comments prior to merging, and feel free to ask someone to merge your PR once the CI checks pass and you're happy with it. Thanks!

[oppiabot]

Hi @masclot, I'm going to mark this PR as stale because it hasn't had any updates for 7 days. If no further activity occurs within 7 days, it will be automatically closed so that others can take up the issue.
If you are still working on this PR, please make a follow-up commit within 3 days (and submit it for review, if applicable). Please also let us know if you are stuck so we can help you!

[masclot]

I addressed the comments and added the landscape images.
PTAL @adhiamboperes

[adhiamboperes]

Thanks @masclot, this LGTM.

[oppiabot]

Unassigning @adhiamboperes since they have already approved the PR.

[oppiabot]

Hi @masclot, this PR is ready to be merged. Please address any remaining comments prior to merging, and feel free to ask someone to merge your PR once the CI checks pass and you're happy with it. Thanks!