[Reader] Update follow tags logic in "Manage Tags & Blogs" screen

[RenanLukas]

Fixes #19353

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To Test:

1. Install JP and sign in;
2. Open Reader;
3. Select "Subscriptions" feed;
4. Tap the tags chip to show the bottom sheet;
5. Tap "Edit" button;
6. Add a new tag;
7. Move back to Reader: the tags chip count should be updated;
8. Repeat steps 4-5;
9. Unsubscribe from a tag: the tag should not be removed from the list, but instead the follow button state should be changed;
10. Move back to Reader: the tags chip count should be updated (which means the unsubscribed tag should not be part of the count);

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Regression Notes

1. Potential unintended areas of impact

   • Tags chip count

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

   • Manual testing

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

   --

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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.

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Testing Checklist:

• WordPress.com sites and self-hosted Jetpack sites.
• Portrait and landscape orientations.
• Light and dark modes.
• Fonts: Larger, smaller and bold text.
• High contrast.
• Talkback.
• Languages with large words or with letters/accents not frequently used in English.
• Right-to-left languages. (Even if translation isn’t complete, formatting should still respect the right-to-left layout)
• Large and small screen sizes. (Tablet and smaller phones)
• Multi-tasking: Split screen and Pop-up view. (Android 10 or higher)

[wpmobilebot]

📲 You can test the changes from this Pull Request in Jetpack by scanning the QR code below to install the corresponding build.

	App Name	Jetpack
	Flavor	Jalapeno
	Build Type	Debug
	Version	pr20171-a02167a
	Commit	a02167a
	Direct Download	jetpack-prototype-build-pr20171-a02167a.apk

Note: Google Login is not supported on these builds.

[wpmobilebot]

📲 You can test the changes from this Pull Request in WordPress by scanning the QR code below to install the corresponding build.

	App Name	WordPress
	Flavor	Jalapeno
	Build Type	Debug
	Version	pr20171-a02167a
	Commit	a02167a
	Direct Download	wordpress-prototype-build-pr20171-a02167a.apk

Note: Google Login is not supported on these builds.

[dangermattic]

	1 Warning
⚠️	PR is not assigned to a milestone.

Generated by 🚫 Danger

[thomashorta]

Thanks for the changes, though I found a blocking bug, since it looks like the button change is only visual, but is not adding back the tag/keeping it when the user taps Subscribe again.

Besides that I also added some minor suggestions.

[peril-wordpress-mobile]

	Warnings
⚠️	PR is not assigned to a milestone.

Generated by 🚫 dangerJS

[RenanLukas]

Thanks for the review, @thomashorta ! The bug should be fixed and I've applied your suggestions 👍

[thomashorta]

I tested it again after the changes and everything looks good to me now!