[docs]: add information about `jsconfig.json` support

Please add information about `jsconfig.json` support in the [Configuration section](https://github.com/import-js/eslint-import-resolver-typescript#configuration) in README.

See https://github.com/import-js/eslint-import-resolver-typescript/pull/161