[Desktop] Load a remote catalog of available regional lists for brave://adblock

[antonok-edm]

Regional lists are currently baked into the adblock-rust repository, which means they're compiled with each version of Brave. Since we ship them from our servers, it makes more sense to serve a dynamic catalog of available regional lists. This way, if a regional list is added, modified, or removed, the list shown in brave://adblock can automatically be updated to reflect the change.

This will also drastically reduce the amount of effort required to ship a filter list change, which currently requires updating/publishing several different repositories (most relevant here are adblock-rust, adblock-rust-ffi, brave-core, and brave-core-crx-packager). This change can make the update process as frictionless as a single commit to adblock-resources.

[btlechowski]

Verification passed on

Brave	1.13.79 Chromium: 85.0.4183.69 (Official Build) dev (64-bit)
Revision	4554ea1a1171bd8d06951a4b7d9336afe6c59967-refs/branch-heads/4183@{#1426}
OS	Ubuntu 18.04 LTS

Verified test plan from brave/brave-core#6125

Verified AdGuard Français is present

Verified EasyList Liste FR - Version: 1.0.677 was installed

Verified AdGuard Français is selected after browser restart

Also verified Polish filters

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Verification passed on

Brave | 1.13.79 Chromium: 85.0.4183.69 (Official Build) dev (64-bit)
-- | --
Revision | 4554ea1a1171bd8d06951a4b7d9336afe6c59967-refs/branch-heads/4183@{#1426}
OS | macOS Version 10.14.6 (Build 18G3020)

Verified test plan from brave/brave-core#6125

Confirmed AdGuard Français is present

Confirmed EasyList Liste FR - Version: 1.0.677 was installed

Confirmed AdGuard Français is still selected after browser restart

Installed 1.12.x and confirmed AdGuard Français is not present

Confirmed it is present after upgrade to 1.13.x

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Verification passed on

Brave | 1.14.59 Chromium: 85.0.4183.69 (Official Build) dev (64-bit)
-- | --
Revision | 4554ea1a1171bd8d06951a4b7d9336afe6c59967-refs/branch-heads/4183@{#1426}
OS | Windows 10 OS Version 1903 (Build 18362.1016)

• Verified test plan from Load regional catalog provided by brave-core-crx-packager brave-core#6125
• Verified AdGuard Français is present
  
• Confirmed EasyList Liste FR - Version: 1.0.677 was installed
  
• Confirmed AdGuard Français is still selected after browser restart