only send igwn-alerts to the {group}_{pipeline} topic

Historically igwn-alert and LVAlert sends out g-event and e-event alerts to topics with the {group}_{pipeline} and {group}_{pipeline}_{search} schema. As more pipelines and searches are added, topic management is becoming a pain across all the GraceDB tiers, especially with the lack of a scriptable API to interact with SCIMMA.

I'm proposing to change the way GraceDB issues alerts to only send to {group}_{pipeline} topics and have users filter on search, if need be. It would have the benefit of simplifying topic management, and also save some milliseconds in dispatching alerts. The alert contents would remain the same. Superevent topics would be unaffected by this change.

Putting out feelers to igwn-alert stakeholders... @deep.chatterjee @cody.messick @nicolas.arnaud @rebecca.ewing would that break your listening processes, if so, would adding an extra filter based on the search in the alert content be too much of a technical burden?