docs: Add one click deploy to readme

[jbgh]

Hey!

We built this one-click deploy link for your users who may not know how to stand up their own infrastructure to easily self-host this.

After deployment, users receive a link like this, which can then be CNAME-ed to any domain:

https://nocodb-1533.dome.tools

Take it for a test run—we're eager to receive your feedback! We're more than willing to maintain this for the long haul, if this is valuable for your users.

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}