feat: add TLD for Slovakia (.sk)

[virpo]

Description of change

Only 21 out of TOP 50 country TLDs are present in the POPULAR_TLDS list (based on these statistics https://domainnamestat.com/statistics/tldtype/country), creating quite a few false positives for loads of countries.

It gets especially embarrassing when a domain such as '.sk' suggest to be changed to '.se', where E sits on the opposite side of the keyboard.

I am adding 'sk' TLD for Slovakia as a quite popular domain, but the list of 29 other domains, that could be added to complete the list for TOP50 sorted alphabetically goes as follows:

['ar', 'au', 'br', 'cc', 'cf', 'cl', 'cn', 'ga', 'gq', 'id', 'in', 'io', 'ir', 'me', 'ml', 'mx', 'nu', 'nz', 'ph', 'pl', 'pw', 'ro', 'tk', 'tw', 'ua', 'vg', 'ws', 'xn', 'za']

Pull-Request Checklist

• [x] Code is up-to-date with the main branch
• [x] npm run lint passes with this change
• [x] npm run test passes with this change
• [x] This pull request links relevant issues as Fixes #0000
• [x] There are new or updated unit tests validating the change
• [x] Documentation has been updated to reflect this change
• [x] The new commits follow conventions outlined in the conventional commit spec

[ferreiro]

@virpo Thanks so much for doing this! I'm going to merge the PR!

From your list, I noticed there are 21 domains that we don't have support to ['ar', 'cf', 'cl', 'cn', 'ga', 'gq', 'ir', 'ml', 'mx', 'nu', 'nz', 'ph', 'pl', 'ro', 'tk', 'tw', 'ua', 'vg', 'ws', 'xn', 'za']

I'm going to create a separate PR adding those.