Is there a best practice for storing certificates (e.g. x509), which include private keys, used in unit tests?

Question

In a software library, I wrote, large parts of the code use x509 certificates for various puprposes like signing documents digitally.

Is there a best practice for storing test certificates used for the unit tests? Should they be stored in git/the same versioning system where the code is?

Answer 1

Certificates are small. And there is no problem with security if they are only used for testing.

So I see no problem storing them in source control.