Repo: Test rule-tester in CI

[JoshuaKGoldberg]

Suggestion

Splitting out from @auvred's #8995 (comment):

Oh, looks like rule-tester is not tested in CI:

typescript-eslint/.github/workflows/ci.yml

Lines 168 to 182 in 4858afd

	package:
	[
	'ast-spec',
	'eslint-plugin',
	'eslint-plugin-internal',
	'parser',
	'repo-tools',
	'rule-schema-to-typescript-types',
	'scope-manager',
	'type-utils',
	'typescript-eslint',
	'typescript-estree',
	'utils',
	'visitor-keys',
	]

Whoops! We should... definitely test this in CI, I'd think?

Co-authored-by: @auvred

[auvred]

Note: we should run both test and test-eslint-base scripts.

Because for test-eslint-base the different test runner is used (Mocha instead of Jest). This is done so because tests/eslint-base/eslint-base.test.js is copied from upstream.

See also #9011