Fix broken links and gallery test

[rcomer]

🚀 Pull Request

Description

Fixed a couple of broken links.

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Consult Iris pull request check list

[bjlittle]

@rcomer I restarted the timed-out cirrus-ci jobs. However, we're getting a gallery graphical test failure:

FAIL: test_plot_wind_speed (gallery_tests.test_plot_wind_speed.TestWindSpeed)

😢

[rcomer]

@bjlittle I'm pretty sure the gallery tests are using an older matplotlib version (can't find a conda list). We removed the old hashes for that wind plot at #4112, because the old images didn't include some lake features that had been explicitly plotted. The test passes locally with an up-to-date environment 👍

[rcomer]

Wind example in stable docs no lakes 👎
Wind example in dev docs lakes 👍

[rcomer]

For #4059 (comment) I also ran the main tests locally under both py3.6 and py3.7. So I'm confident all is well.

[rcomer]

@bjlittle please see additional commit to blacken those lake edges. Gallery tests now passing.

😎

[bjlittle]

@rcomer Clearly we're not going to get CI to work for py36 or py37 on v3.0.x due to known reasons... so I'm going to test your branch locally instead for both Python versions.

I'm happy to merge with CI failures, but local passes 👍

[rcomer]

@bjlittle I think we'll need to pull in #4139 to get the tests passing with a fully up-to-date environment 😢

I'm on leave for the next week and can't promise to give this attention. Please feel free to do whatever you like with my branches to get v3.0.2 over the line.

[rcomer]

Superseded by #4154