Improve falcon-instrumentation `_handle_exception` method to remove pylint disables

[emdneto]

Fix falcon-instrumentation _handle_exception method to remove pylint disables

Originally posted by @emdneto in #4193

[srikaaviya]

Hi @emdneto, I'd like to work on this issue.

My plan is to conditionally define handle_exception based on _falcon_version, using the correct parameter names for each version. This will remove the need for the pylint: disable=C0103,W0237,W1114 comments.

I'll test locally and open a PR.