Feature: Add pool incentivisation setup functionallity

[MbBrainz]

As pools and their incentives are core part of the Dex, it would be a valuable addition to the testsuite to provide a convenience method for setting up pool incentives. Ideally, this would provide the complete logic for both setting up the gauges, the incentive params for that gauge and the token distribution setup.

[iboss-ptk]

I don't have much capacity rn, contribution is welcome :)