Slack alerts in threads: add option to enable or disable it

[rodolfoBee]

Problem Statement

With the addition of Slack threads for metric alerts, when the same issue triggers an alert multiple times all messages are in the same thread.

Some users like this behaviour, some want to see all messages in the channel .

A recent change made all messages to also be posted in the channel, not only in the thread.

Solution Brainstorm

Make this behaviour customisable:
By default send only to thread with the option to also send to channel, or vice-versa.

Product Area

Settings - Integrations

[getsantry]

Assigning to @getsentry/support for routing ⏲️

[getsantry]

Routing to @getsentry/product-owners-settings-integrations for triage ⏲️

[Dhrumil-Sentry]

This is a fair request and we're currently working on providing options so users can turn off any use of threads for issue or metric alerts