Unable to unfollow migrated Planet Mozilla atom feed in v2

[stephendonner]

Description

Unable to unfollow migrated Planet Mozilla atom feed in v2

Steps to Reproduce

1. install 1.47.14
2. launch Brave
3. load https://planet.mozilla.org/
4. copy the Atom feed link: https://planet.mozilla.org/atom.xml
5. click on Customize
6. click on Brave News
7. enter https://planet.mozilla.org/atom.xml under Feed URL and click on Add Source
8. wait a bit (big feed)
9. load brave://flags
10. set brave://flags/#brave-news-v2 to Enabled
11. click on Relaunch
12. open a new-tab page
13. click on Customize
14. click on Turn on Brave News
15. hover to the right of Planet Mozilla in the Top Sources section
16. click Unfollow

Actual result:

Nothing happens

Expected result:

Should remove Planet Mozilla from the sources list

Note: I am still able to remove Top Sources

Reproduces how often:

100%

Brave version (brave://version info)

Brave	1.47.14 Chromium: 107.0.5304.62 (Official Build) nightly (x86_64)
Revision	1eec40d3a5764881c92085aaee66d25075c159aa-refs/branch-heads/5304@{#942}
OS	macOS Version 11.7.1 (Build 20G918)

Version/Channel Information:

• Can you reproduce this issue with the current release?
• Can you reproduce this issue with the beta channel?
• Can you reproduce this issue with the nightly channel?

Other Additional Information:

• Does the issue resolve itself when disabling Brave Shields?
• Does the issue resolve itself when disabling Brave Rewards?
• Is the issue reproducible on the latest version of Chrome?

Miscellaneous Information:

cc @petemill @fallaciousreasoning @rebron @brave/qa-team

[fallaciousreasoning]

Pretty sure this is a duplicate of #26196

Should be fixed in 1.47.17 (I'm uplifting to 1.46.x)