SSIS error: Drop faield for user

I was trying to drop a user from SSIDB database and I encountered the following error -

The database principal has granted or denied permission to catalog objects in the database and cannot be dropped. The transaction ended in the trigger. The batch has been aborted. (Microsoft SQL Server, Error: 27226)


I ran the following query to find the permission of the user I am trying to drop


use SSISDB
GO

SELECT TOP 1000 [object_type]

,[object_id]

,[principal_id]

,[permission_type]

,[is_deny]

,[grantor_id]

, 'EXEC catalog.revoke_permission @object_type=' + CAST([object_type] AS VARCHAR)

+ ', @object_id=' + CAST([object_id] AS VARCHAR)

+ ', @principal_id=' + CAST(principal_id AS VARCHAR)

+ ', @permission_type=' + CAST(permission_type AS VARCHAR) [execute this]

FROM [SSISDB].[catalog].[explicit_object_permissions]

WHERE principal_id = USER_ID('usertodrop')


Then copied the contents of the [execute this] column in a new query window and executed it against the SSISDB database which revokes the permission .
Then I was able to drop the user.