benchmark: add trailing newline for consistency

PR-URL: https://github.com/nodejs/node/pull/9410
Fixes: https://github.com/nodejs/node/issues/9402
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Sakthipriyan Vairamani <thechargingvolcano@gmail.com>
Reviewed-By: Gibson Fahnestock <gibfahn@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Minwoo Jung <jmwsoft@gmail.com>

benchmark/README.md

@@ -352,4 +352,4 @@ Supported options keys are:
 [autocannon]: https://github.com/mcollina/autocannon
 [wrk]: https://github.com/wg/wrk
 [t-test]: https://en.wikipedia.org/wiki/Student%27s_t-test#Equal_or_unequal_sample_sizes.2C_unequal_variances
-[git-for-windows]: http://git-scm.com/download/win
+[git-for-windows]: http://git-scm.com/download/win