Event subscription handler missing (MissingEventSubscriptionHandler)

Type	Scope	Severity	Activated by default	Minutes to fix	Tags
`Error`	`BSL`	`Blocker`	`Yes`	`5`	`error`

Description

If the handler for the "event subscription" is not filled or does not exist, then an error will occur in the application.

Note: Diagnostics attaches notes to the "session module".

// BSLLS:MissingEventSubscriptionHandler-off
// BSLLS:MissingEventSubscriptionHandler-on

"MissingEventSubscriptionHandler": false