feat: add fee skipping

[byte-bandit]

Related Github tickets

• [PALOMA] Add Module to ignore transaction fees using antehandler so that transaction fees are removed from Paloma. VolumeFi/paloma#2466

Background

This change introduces as custom TxFeeChecker implementation, which simply returns an empty fee for every transaction, as well as a constant priority.

Merging this change will lead to an equal transaction prioritization across Paloma, without the option to incentivize validators to include a transaction in an earlier block.

Testing completed

• test coverage exists or has been added/updated
• tested in a private testnet

Breaking changes

• I have checked my code for breaking changes
• If there are breaking changes, there is a supporting migration.

[taariq]

LFG!