While running the test suite locally, I noticed several errors/failures in ClientSideEncryptionSpecTest due to mongocryptd being unavailable.

It appears that skipIfClientSideEncryptionIsNotSupported only checks the server's FCV and whether PHPC has libmongocrypt compiled in. It would be reasonable to also ensure mongocryptd is running, or perhaps consult an environment variable to catch a case where it should be running but is otherwise inaccessible (where we'd want tests to run and fail accordingly).