Channels in Brave News are not translated

[fallaciousreasoning]

We should add translations for channels in Brave News. The V1 UI doesn't support this at all.

[kjozwiak]

The above will require 1.46.100 or higher for 1.46.x verification 👍

[stephendonner]

Verified PASSED using

Brave	1.46.100 Chromium: 107.0.5304.91 (Official Build) dev (x86_64)
Revision	3d5948960d62418160796d5831a4d2d7d6c90fa8-refs/branch-heads/5304@{#1097}
OS	macOS Version 11.7.1 (Build 20G918)

Steps:

1. set my macOS system language to Russian, and German (separately, of course)
2. installed 1.46.100
3. launched Brave
4. opened brave://flags
5. set brave://flags/#brave-news-v2 to Enabled
6. clicked Relaunch
7. opened a new-tab page
8. clicked on Customize
9. clicked on Brave News
10. examined the Customize Brave News dialog

Confirmed Crypto became криптовалюта in Russian, and Krypto in German

Russian	German

[srirambv]

Removing Android label as this doesn't work on Android. There is no V2 UI and translation is not done for existing sources. Added follow up/Android specific issue #26660