Rename files with a clashing namespace

[ArBridgeman]

Summary

While working on #728, it was noted that 3 of our files within sqlalchemy-exasol clash with the namespaces of packages were are using. This is problematic if users execute code examples in an IDE, as the IDE (like PyCharm), might erroneously think that our code is the source for functions. The renaming should be more thought out than what was put here, as those were quickly done to make something work.

❗ Custom Setup
types.py to exasol_types.py
warnings.py to exasol_warnings.py
websocket.py to exasol_websocket.py
__init__.py adapted for websocket change
pyproject.toml adapted for websocket change