🚀 Feature: Also delete existing Mocha options file in migration, if it exists

[JoshuaKGoldberg]

Bug Report Checklist

• I have pulled the latest main branch of the repository.
• I have searched for related issues and found none that matched my issue.

Overview

Right now, --mode migrate will attempt to delete any existing Jest config file:

create-typescript-app/src/steps/clearUnnecessaryFiles.ts

Line 9 in 592b0c8

...extensions("jest.config", "cjs", "js", "json", "mjs", "ts"),

Fun fact: the venerable Mocha test framework has config file support too! https://mochajs.org/#configuring-mocha-nodejs

Let's have files like .mocharc.js, .mocharc.yml, etc. be removed during migration too.

Additional Info

Other test frameworks -Ava, QUnit, etc.- could be migrated too. I'd welcome anybody using those to file a new issue requesting that as a feature.

Similar issue for Mocha: #1374