Evaluate performance impact of `deprecated` decorator in hot codepath

There is one `deprecated` decorator in the hot code path which was initially moved to the class level to reduce performance impact, and which I've moved back to the method level but _commented-out_ to avoid any performance impact. Since migrating from the `Deprecated` third party library to the [PEP 702](https://peps.python.org/pep-0702/#backwards-compatibility) native support for `@deprecated` decorators, we might be in a better situation now with performance, but I didn't want to take a risk. I also didn't want to trigger a deprecated warning on the whole class if only one method is deprecated.

https://github.com/airbytehq/airbyte-python-cdk/blob/bd2e5affd196b2f36dfc0fb8bbbae07771dde188/airbyte_cdk/sources/streams/core.py#L434-L444