[CT-1612] Add deprecation decorator for functions

[emmyoop]

Create a decorator that can be added to functions to mark them as deprecated.

Related to #6347 as we need to make the functions that currently trigger exceptions as deprecated for all the adapters that may be using them.

Open questions:

• What standard info to include with deprecation?
• When should the exception functions actually be deprecated - 1 or 2 versions?

[justbldwn]

hi @emmyoop! i see this is self-assigned - are you looking for PR's for this issue? or have you already started work on this? just checking before possibly contributing 👍

[emmyoop]

@justbldwn I'll be working on this over our next sprint. Thanks for checking in though!