token-client: Add compute unit price and limit fields

[joncinque]

Problem

The token-cli doesn't support priority fees.

Solution

As the first part of #6492, add the ability to specify a compute unit limit on the token-client directly.

Note: Some of the parts of setting the compute unit limit by hand in the tests can be removed once we dynamically calculate the compute unit limit based on simulation, for part 3 of #6492

[CriesofCarrots]

So much cleaner too :)