Display note for deprecated irdb modes

[oczoske]

UserCommands.set_modes() displays a deprecation note if the parameter deprecate is set in the irdb mode definition.
UserCommands.list_modes() adds "(deprecated)" to the description of such modes.

[codecov]

Codecov Report

Patch coverage: 50.00% and project coverage change: -0.01 ⚠️

Comparison is base (a0e08a8) 80.86% compared to head (e9a61dd) 80.85%.

Additional details and impacted files

@@              Coverage Diff               @@
##           dev_master     #251      +/-   ##
==============================================
- Coverage       80.86%   80.85%   -0.01%     
==============================================
  Files             143      143              
  Lines           14658    14662       +4     
==============================================
+ Hits            11853    11855       +2     
- Misses           2805     2807       +2     

Impacted Files	Coverage Δ
scopesim/commands/user_commands.py	87.50% <50.00%> (-1.02%)	⬇️

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[teutoburg]

The few tests that still fail now are AFAIK all related to GitHub API timeouts. Can be ignored.

[hugobuddel]

Good! I'll go ahead and merge.

Some ideas to formalize this further, but we can do that later, if necessary:

Actively use DeprecationWarning, because that is, I think, the Pythonic way to remind users of deprecation.

warnings.warn(f"Mode {mode} is deprecated.", category=DeprecationWarning)

For the users we could add two pieces of information:

• How to move away from the deprecation, e.g. "You probably want to use mode XYZ instead".
• A plan for when the deprecated mode will be removed. But we probably won't know that, because of our uncertain plans for the wheels.

[oczoske]

Note that this (set_modes, actually) reads a full deprecation message from the irdb (see irdb/MICADO/default.yaml), which ideally explains why the mode is deprecated and what to use instead. The current formulation and formatting is not perfect but hopefully good enough. The category looks like a good extension, though.