doc: add FlowG to "Projects Using Badger" section of the README (#2180)

**Description**

It's been a while now since we've been working on
[FlowG](https://github.com/link-society/flowg), and it's thanks to this
project, great work <3

It would be awesome to be listed in your README. Thank you.

**Checklist**

N/A

Author: linkdd

README.md

@@ -277,6 +277,7 @@ Below is a list of known projects that use Badger:
   and badger db
 - [MightyMap](https://github.com/thisisdevelopment/mightymap) - Mightymap: Conveys both robustness
   and high capability, fitting for a powerful concurrent map.
+- [FlowG](https://github.com/link-society/flowg) - A low-code log processing facility
 
 If you are using Badger in a project please send a pull request to add it to the list.