breaking change: deprecate `cnb_classification` dataset

[jdhoffa]

Relates to #327

FYI @jacobvjk, I plan to deprecate these datasets properly, which means including a release where we just warn that they will be deprecated.

AB#10173

[AlexAxthelm]

@jdhoffa do we have a rough timeframe (on a calendar) when we expect to fully deprecate?

[jdhoffa]

Nope, but I think if we do my quarterly release schedule, then next release is end of Q1 (end of March). That will mark beginning of deprecation.

Following release is end of Q2 (so end of June?)

I guess end of June would be when they are hard deprecated? I will update the warning message and add an ADO ticket

[AlexAxthelm]

Maybe have something along the lines of

"foo will be available until 2024-06-01. In releases of r2dii.data after that date, it will be unavailable. Please use bar instead. See this blog post for more information."

So users know have some idea of when they would need to transition by?

[jdhoffa]

Deprecation warning is already there. Following the lifecycle style deprecation process:
https://github.com/RMI-PACTA/r2dii.data/pull/331/files

I just need to update the "date"

[jdhoffa]

@AlexAxthelm do you think "expected in 2024Q2 release" would be too vague actually? I would tend to prefer that... especially given that the proposed "quarterly release" cadence is really just quarterly and has no specific date or month focus yet...

Gives us a bit of flexibility while still giving the user an idea of when things will change.

[jdhoffa]

ADO ticket in proposal of next quarter's KRs involving completing the deprecation process:
https://dev.azure.com/RMI-PACTA/2DegreesInvesting/_workitems/edit/9711

[AlexAxthelm]

"expected in 2024Q2 release" would be too vague actually?

I think I shouldn't write user-facing messages. But that's reasonable enough from my side.

cc @hodie