Increase zh tourney freq

[isaacl]

Fixes #15861

[isaacl]

Note: this is just a suggestion -- I'd like feedback on this new schedule

[isaacl]

The idea is:

• threecheck, Chess960 and KoTH are the most similar to regular chess, so grouping them together. Possibly there should be more of these tourneys too though.
• antichess is not a popular variant, so decrease its freq, and couple it to the other esoteric variants (racing kings, horde)
• zh is the most popular variant after 960, so incr freq.

I haven't done anything explicit about avoiding Atomic 5 0. In general, another issue is the speed selectors use mod 7, and that means speed cases 0-2 happen more frequently than cases 3-6

[isaacl]

Will PR a different tourney adjustment patch based on feedback

[cFlour]

• antichess is not a popular variant, so decrease its freq, and couple it to the other esoteric variants (racing kings, horde)

Where are you getting this information from? Antichess is the most popular variant on lichess, with 100+ people joining each hourly.

[isaacl]

@cFlour yes understood. That's why this PR is closed in favor of one which will not reduce antichess tourneys