[Desktop] Update favicons for internal pages

[rebron]

Description

Follow-up to: #8492.

Update favicons for:

• brave://settings
• brave://history
• brave://downloads

Steps to Reproduce

1. Go to the internal pages above.
2. Notice they're using chromium provided icons
3. Expected result is that icons are Brave provided favicons

Actual result:

Designs (expected result):

Reproduces how often:

Easily.

Brave version (brave://version info)

Version/Channel Information:

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

Other Additional Information:

• Does the issue resolve itself when disabling Brave Shields? No
• Does the issue resolve itself when disabling Brave Rewards? No
• Is the issue reproducible on the latest version of Chrome? No

Miscellaneous Information:

[rebron]

cc: @simonhong

[karenkliu]

@simonhong The icons in Figma are all 24x24. Let me know if you need these in a different size or color.

Settings: https://www.figma.com/file/xWGBM3qWbu3RLuZqZGwynk/Icons?node-id=124%3A10694

History: https://www.figma.com/file/xWGBM3qWbu3RLuZqZGwynk/Icons?node-id=124%3A10694

Downloads: https://www.figma.com/file/xWGBM3qWbu3RLuZqZGwynk/Icons?node-id=124%3A10694

[GeetaSarvadnya]

Verification passed on

Brave | 1.11.65 Chromium: 83.0.4103.97 (Official Build) dev (64-bit)
-- | --
Revision | 326d148b9655369b86498d9ecca39f63dd2bdd2d-refs/branch-heads/4103@{#657}
OS | Windows 10 OS Version 1903 (Build 18362.30)

• Verified the STR from the description
• Installed 1.10.x and upgraded to 1.11.x and verified that settings, download and history icons are replaced with brave branded favicons
  

---

Verified passed with

Brave | 1.11.78 Chromium: 83.0.4103.116 (Official Build) dev (64-bit)
-- | --
Revision | 8f0c18b4dca9b6699eb629be0f51810c24fb6428-refs/branch-heads/4103@{#716}
OS | macOS Version 10.14.6 (Build 18G3020)

1.10.x favicons for Settings, Downloads, Bookmarks, History:

1.11.x favicons for Settings, Downloads, Bookmarks, History:

---

Verified passed with

Brave	1.11.84 Chromium: 83.0.4103.116 (Official Build) dev (64-bit)
Revision	8f0c18b4dca9b6699eb629be0f51810c24fb6428-refs/branch-heads/4103@{#716}
OS	Linux

1.11.x favicons for Settings, Bookmarks, Downloads, History (dark)

1.11.x favicons for Settings, Bookmarks, Downloads, History (light)