skip recipe filler tests until we have a new release since GA tests are failing

[valeriupredoi]

Since the GA development tests are using the latest esmvalcore development branch, and the recipe filler is configured for the (lagging behind) release, GA full development tests are failing, that, in turn, may mask an issue with the latest esmvalcore development branch + esmvaltool. Discussed with @schlunma in #2088 👍 We'll have to reactivate them when we release esmvalcore 2.3.0 and change the setup in the recipe filler to use the new config module

Closes #2088

[schlunma]

Nice one! Two suggestions:

1. Would it make sense to use skipif with version.parse(esmvalcore.__version__) < version.parse(2.3.0) using packaging.version.parse so we are reminded to fix the test for the new release?
2. Can you skip the other two fails too:

==================================== ERRORS ====================================
______ ERROR collecting esmvaltool/cmorizers/obs/cmorize_obs_cds_uerra.py ______
esmvaltool/cmorizers/obs/cmorize_obs_cds_uerra.py:45: in <module>
    from esmvalcore.preprocessor._regrid import _stock_cube
E   ImportError: cannot import name '_stock_cube' from 'esmvalcore.preprocessor._regrid' (/home/runner/work/ESMValTool/ESMValCore/esmvalcore/preprocessor/_regrid.py)
______ ERROR collecting esmvaltool/cmorizers/obs/cmorize_obs_cds_uerra.py ______
esmvaltool/cmorizers/obs/cmorize_obs_cds_uerra.py:45: in <module>
    from esmvalcore.preprocessor._regrid import _stock_cube
E   ImportError: cannot import name '_stock_cube' from 'esmvalcore.preprocessor._regrid' (/home/runner/work/ESMValTool/ESMValCore/esmvalcore/preprocessor/_regrid.py)

[valeriupredoi]

cheers Manu, good point! for 1. I am going to plug the skip now, for 2. I moved the private import via drag and dropping the functions in #2087

[schlunma]

Nice! 🍺

[valeriupredoi]

danke sehr, Herr Doktor Manu 😁