refactor: use macros for RequestBuilderError

[reez]

Description

This should be the last Error needing to be removed from UDL in proc macro conversion.

Notes to the reviewers

I needed #791 merged before I did this, so I just merged 791 so this PR should be good to go now.

Changelog notice

Checklists

All Submissions:

• I've signed all my commits
• I followed the contribution guidelines
• I ran cargo fmt and cargo clippy before committing

New Features:

• I've added tests for the new feature
• I've added docs for the new feature

Bugfixes:

• This pull request breaks the existing API
• I've added tests to reproduce the issue which are now passing
• I'm linking the issue being fixed by this PR

[ItoroD]

ACK 528bc09