* Adding configuration example for retain modes
Reading the documentation on its own didn't help me but when I found https://github.com/blakeblackshear/frigate/discussions/2447 I was able to understand how to add this to my configuration. I've added the example given in that discussion to help future readers of the page.
* Update record.md
Added suggested changes and have also added wording beneath the example mentioning the configuration can be added on a per camera basis.
Have also built on the example to add object specific retentions timings - Not sure if it would be preferred to have it all within one example to not complicate things?
Let me know your thoughts
* Update record.md
Created Object Specific Retention header
* Typo
Co-authored-by: Blake Blackshear <blake@frigate.video>
