CCleaner won't work on my Mac

I have paid for CCleaner / Mac edition, but Mac blocks it says

“CCleaner” can’t be opened because Apple cannot check it for malicious software.

This software needs to be updated. Contact the developer for more information.

See here

https://community.ccleaner.com/topic/56699-catalina-apple-cannot-check-it-for-malicious-software-error-solution/