Use nearest scheme to avoid interpolation errors with masked data in regression test

[stefsmeets]

Description

This PR changes the regridder from Linear to a Nearest scheme to avoid interpolation errors on masked arrays. It also updates the regression data. This fixes an issue with the regression test that makes it difficult to compare between branches.

For more info on why this happens, see also #593

• Closes: Linear regridder causes interpolation errors for masked data in sample data tests #1014

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[stefsmeets]

Hi @valeriupredoi , could you have a look at this one? 🚀

[valeriupredoi]

looks good, man 👍

[valeriupredoi]

@stefsmeets could you please fix the failing multimodel test mate https://app.circleci.com/pipelines/github/ESMValGroup/ESMValCore/4339/workflows/a42839e2-f294-4223-834b-0afec25fda4f/jobs/20245
Always remember to run the tests locally too, since our test CI is a bit en retard and builds only off master

[valeriupredoi]

friendly ping @stefsmeets 👍

[valeriupredoi]

friendly ping @stefsmeets +1

nevermind, that's happening coz the actual sample data has now changed, the Github Actions pass well, @bouweandela when is the sample data changed in the test container?

[stefsmeets]

Yeah, I noticed one test oddly failed in your PR. I just re-ran it before I did the review to see what happened. Not entirely sure why it magically got fixed, will keep an eye on it 👍