[ ENH ] Add add_comment keyword argument to PerformIncidentAction operation

[jshcodes]

          @jshcodes , sorry for commenting on a closed issue, but I just passed by as I saw the documentation at [falconpy.io](https://falconpy.io/Service-Collections/Incidents.html#performincidentaction) still states the same as the documentarion at [Swagger](https://assets.falcon.eu-1.crowdstrike.com/support/api/swagger-eu.html#/incidents/PerformIncidentAction);

Perform a set of actions on one or more incidents, such as adding tags or comments or updating the incident name or description

After some digging, I found that it is the documentation at https://falcon.eu-1.crowdstrike.com/documentation/86/detections-monitoring-apis#modify-incidents that is lacking details of the available action paramters. It is in fact possible to add a comment to an incident by using the action parameter name: "add_comment".

I guess it would be a good idea to update the documentations around :) And it would also be nice to have an own keyword argument for add_comment ;)

Originally posted by @morcef in #776 (comment)