Fix: stable market tiers

[Arrowana]

What is the cost of comparing all those pubkeys? Are we worried?

spl-token seems to use sol_memcmp to do it "cheap"
https://github.com/solana-labs/solana-program-library/blob/master/token/program/src/processor.rs#L872-L876

[armaniferrante]

What is the cost of comparing all those pubkeys? Are we worried?

spl-token seems to use sol_memcmp to do it "cheap" https://github.com/solana-labs/solana-program-library/blob/master/token/program/src/processor.rs#L872-L876

Should be sensitive to this, but likely ok for now. The next version should do this right, but for now there's not a great way to do this in a non breaking way.