[docs/config.md]Fix syntax highlighting + clarify :frontend_configuration
Hey,
-
Fix syntax highlighting:
```exs
isn't valid and some code were missing highlighting. -
clarify :frontend_configuration: clarified a little bit and added a note about how having
:fe
dismiss:frontend_configuration
Modified file is visually accessible here : https://pleroma-docs.krkrkr.org/config.html
I don't have much time atm so i feel like for small changes like this one it might be simpler if i just gave away .patch files on irc instead of creating merge requests for little things.
Have a good day!