Restore support for scalar cubes to time selection preprocessor functions

[bouweandela]

Description

Restore support for scalar cubes to time selection preprocessor functions.

Closes #1743

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[codecov]

Codecov Report

Merging #1750 (db3ff99) into main (77612eb) will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main    #1750   +/-   ##
=======================================
  Coverage   91.17%   91.17%           
=======================================
  Files         202      202           
  Lines       10887    10890    +3     
=======================================
+ Hits         9926     9929    +3     
  Misses        961      961           

Impacted Files	Coverage Δ
esmvalcore/preprocessor/_time.py	97.70% <100.00%> (+0.01%)	⬆️

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[schlunma]

Looks great, thanks @bouweandela! Tested successfully on real data with resample_time.

[valeriupredoi]

very cool! I am going to plug this in the next rc (which is probably gonna be the stable version) 🥳

[valeriupredoi]

@bouweandela you mind turning the GA just for a fleeing second pls so we don't run into the lower Pythons complaining again?

[bouweandela]

The problem was with type hints, using | instead of typing.Union is only supported since Python 3.10. Since this pull request does not introduce any type hints, it seems unlikely that there will be a problem.

Anyway, didn't you configure the GitHub actions such that you could trigger them with a comment or something?

[valeriupredoi]

aha gotcha! Gonna merge w/o it then, I'll keep an eye for hints of failure 🐍 Yeah I did, but I had to deactivate the test - you can activate the test, trigger them by comment (beats me what comment it was though 😆 _, then deactivate the test again, coz if it stays active then that will run on an any other PR - GitHub devs were extremely useful and told me that bug will not be fixed in the near future. Thanks, GitHub!

[valeriupredoi]

cheers @bouweandela 🍺