Moving diagnostics into a service (#14832)

* Moving diagnostics into a service

* Fixing golint checks

* Fixing tests

* Renaming from diagnostics to telemetry

* Adding missing files

* Initializing telemetry earlier in the server startup

* Fixing tests

* Adding a log for the telemetryID initialization error

* Addressing PR review comments

* Fixing merge problem

* Removing some extra Diagnostics mentions

* Making tests pass

model/migration.go

@@ -4,6 +4,7 @@
 package model
 
 const (
+	ADVANCED_PERMISSIONS_MIGRATION_KEY         = "AdvancedPermissionsMigrationComplete"
 	MIGRATION_KEY_ADVANCED_PERMISSIONS_PHASE_2 = "migration_advanced_permissions_phase_2"
 
 	MIGRATION_KEY_EMOJI_PERMISSIONS_SPLIT                     = "emoji_permissions_split"