Action field in Recommendation events have a blank/null value

[romartin]

See https://issues.redhat.com/browse/AAP-24192

Description

The goal is to provide some quick fix some more common use cases, where action feedback is being handled in a wrong way, without a need for a bigger refactoring.

This PR improves the lifecycle of completion / feedback events , by assuming that several completion requests can be sent, before the suggestion is displayed to the user, this way:

• Guarantees that for each successful (HTTP 200) completion request, it will end up on an action feedback event, can be accepted, rejected or ignored
• Guarantees that for failed (non-200) completion requests, no action feedback is sent at all

Tested use cases

• Accepting/rejecting a suggestion both by clicking on the buttons (accept, acceptKey) also by using keys (Tab, Esc)
• Ignored action feedback sent, before suggestion presented, but user pressed some key (eg: whitespace)
• Ignored action feedback sent, once suggestion presented, but user moved to another window, or lost the focus
• Rejected action feedback sent, once suggestion presented, but user pressed some key (eg: whitespace)
• Tested he fix for the steps to reproduce described in https://issues.redhat.com/browse/AAP-24192

TODO: Update/add unit tests