Compare datetimes instead of strings in _fixes/cmip5/test_access1_X.py

[valeriupredoi]

Description

Got rid of num2date calls that change the outputted string formatted date everytime there's a new release of cf_units and compare datime objects straight out the box.

Closes #1158

Link to documentation:

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[zklaus]

As @trexfeathers pointed out in the issue, we don't know what we will get back from num2date. That maybe datetime.datetime or cftime.datetime. That makes the comparison with always datetime.datetime fragile, particularly since we use a date long before the Gregorian calendar. Maybe we should use the suggested only_use_cftime_datetimes=True kwarg to num2date and import cftime.datetime instead?

[valeriupredoi]

@zklaus fragile is good for testing - that prompts us to look into what's the problem. The thing is, we don't use only cf_time.datetime - we use mostly datetime.datetime in Core, so a test fail would give us a hint there is an issue with the comparison that might stem from different behaviour of cf_time/units vs the datetime module - I think it's good like this, what do you think?

[zklaus]

Alright. Sounds good. Let me do a formal review.

[zklaus]

Remove this?

[valeriupredoi]

on it right after the last OSX test passes

[zklaus]

Could you please also go through the checklist and assign labels?

[valeriupredoi]

all tests had passed, removed the call to test on branch, ready to go go Klaus 🏁

[zklaus]

Just finish up the checklist please, possibly by removing or striking out not applicable items.

[valeriupredoi]

done, cheers for the review, Klaus! I think we're now good in terms of all the test fails, on various platforms, a release will be clean 🥇

[zklaus]

Cheers V, great work these days! (And all others too, of course 😝 )

[valeriupredoi]

🍺 🍺 🍺