pg_dump_anon and DbaaS

Hello,

Thanks for your great work. I've deployed postgresql anonymizer on a google cloud postgresql to dump an anonymous database for our staging/test.

I've been using pg_anon_dump wich does verify that the extension is installed. But the extension can't be installed with DbaaS and after removing that check I've found that pg_dump_anon can work with the cloud install (without the extension).

I'm willing to contribute a PR to the scripts. What would be the best way to check if anon is installed without checking the extension ?

Thanks