What problem does this feature solve?

Currently, the include directive can only be overridden via the config file, not through CLI arguments.

What does the proposed API look like?

The user shoud be able to customize the unit test file name regexps/globs via CLI params, to make this consistent with other test runners.

npx rstest run --include src/**/*.tests.tsx --include src/**/*.specs.tsx

This makes migration to rstest easier for projects that already follow their own naming convention for test files.