Verify removal of CookieListDefaultStudy on main

[antonok-edm]

CookieListDefaultStudy is being removed from production in #432. It's already not in main for some reason, but we'd like to double-check that everything works as expected on main before merging #432.

[kjozwiak]

QA has verified BraveAdblockCookieListOptInReleaseStudy pretty extensively while CookieListDefaultStudy was already removed from main as per the #377 (comment) & #377 (comment). Quickly went through a spot check and ensured that BraveAdblockCookieListOptInReleaseStudy was working as per the following:

Verification PASSED on Win 11 x64 using the following build(s):

Brave | 1.45.118 Chromium: 107.0.5304.91 (Official Build) (64-bit)
-- | --
Revision | 3d5948960d62418160796d5831a4d2d7d6c90fa8-refs/branch-heads/5304@{#1097}
OS | Windows 11 Version 22H2 (Build 22621.755)

Example	Example

Verification PASSED on Samsung Galaxy S10+ running Android 12 using the following build(s):

Brave | 1.45.120 Chromium: 107.0.5304.91 (Official Build) (64-bit)
--- | ---
Revision | 3d5948960d62418160796d5831a4d2d7d6c90fa8-refs/branch-heads/5304@{#1097}
OS | Android 12; Build/SP1A.210812.016

Example	Example	Example