[PLT-8173] Strip the post_ prefix on incoming webhook overrides. (#8019)

store/sqlstore/upgrade.go

@@ -328,8 +328,12 @@ func UpgradeDatabaseToVersion46(sqlStore SqlStore) {
 	//TODO: Uncomment folowing when version 4.6 is released
 	//if shouldPerformUpgrade(sqlStore, VERSION_4_5_0, VERSION_4_6_0) {
 
-	sqlStore.CreateColumnIfNotExists("IncomingWebhooks", "PostUsername", "varchar(64)", "varchar(64)", "")
-	sqlStore.CreateColumnIfNotExists("IncomingWebhooks", "PostIconURL", "varchar(1024)", "varchar(1024)", "")
+	//TODO: Remove these remove calls when version 4.6 is released. The columns were renamed.
+	sqlStore.RemoveColumnIfExists("IncomingWebhooks", "PostUsername")
+	sqlStore.RemoveColumnIfExists("IncomingWebhooks", "PostIconURL")
+
+	sqlStore.CreateColumnIfNotExists("IncomingWebhooks", "Username", "varchar(64)", "varchar(64)", "")
+	sqlStore.CreateColumnIfNotExists("IncomingWebhooks", "IconURL", "varchar(1024)", "varchar(1024)", "")
 
 	//saveSchemaVersion(sqlStore, VERSION_4_6_0)
 	//}