Fix README.md

[YutaSugimura]

The incorrect port number for localhost.

[google-cla[bot]]

Thanks for your pull request! It looks like this may be your first contribution to a Google open source project. Before we can look at your pull request, you'll need to sign a Contributor License Agreement (CLA).

View this failed invocation of the CLA check for more information.

For the most up to date status, view the checks section at the bottom of the pull request.

[Jasonkoolman]

The current README should be correct. Port 5000 is used, not port 5005