Fix renter not being able to renew empty contracts

MERGE REQUEST

MR Guidelines

Overview

Example for Visual Changes

This MR upgrades the rhp3 renew protocol to also be able to renew a contract if the renter passes an empty price table due to not being able to fetch a valid one. e.g. if it ran out of money to do so.

It also adds some rudimentary gouging until we have time to roll out more advanced gouging.

Checklist

Review and complete the checklist to ensure that the MR is complete before assigned to an approver.

• All new methods or updated methods have clear docstrings
• Testing added or updated for new methods
• Any new packages are added to Makefile and .gitlab-ci.yml
• API documentation updated for API updates
• Module README.md updated for changes to workflow
• Issue added to Sia-UI repo for new supporting features
• Changelog File Created

Issues Closed