Update from old 'cx_Oracle' to 'oracledb'

[cjbj]

SQLAlchemy 2 supports the latest Oracle Database driver which was renamed to python-oracledb from cx_Oracle a couple of years ago. The new version is a 'thin' driver so a simple 'pip install oracledb' installs all that is needed to connect to Oracle Database.

The test suite references to cx_Oracle should be updated to the new module name 'oracledb' as appropriate when SQLAlchemy 2 is in use. https://github.com/search?q=repo%3Agreat-expectations%2Fgreat_expectations%20oracle&type=code

The engine creation prefix for Oracle Database is 'oracle+oracledb://'

If you want an Oracle DB container for testing, use https://hub.docker.com/r/gvenzl/oracle-free