Fix render tests due to environment change

[HarelM]

Launch Checklist

The following indicate a change in the ubuntu environment yesterday:
https://github.com/actions/virtual-environments/blob/main/images/linux/Ubuntu1804-Readme.md
Which I believe is the root cause of the render test failure.
I'll see if I can make them pass as part of this PR...

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[github-actions]

Bundle size report:

Size Change: 0 B
Total Size Before: 194 kB
Total Size After: 194 kB

Output file	Before	After	Change
maplibre-gl.js	185 kB	185 kB	0 B
maplibre-gl.css	9.25 kB	9.25 kB	0 B

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No major changes

[HarelM]

@astridx in the above run I've added to the artifacts the failed tests with the actual image that was created in the CI server while running the 6 failing tests.
The html file can be found here:
https://github.com/maplibre/maplibre-gl-js/actions/runs/1864381789
When I open it and save the image instead of the expected image git doesn't think there's a change in the file for some reason.
Can you see if you can help out and maybe force git somehow to change the files?

If this doesn't work we can change the threshold a bit I guess...?
Any help would be appreciated...

[astridx]

@HarelM I'm afraid I don't understand the problem exactly.

(You probably ask me because I work with Ubuntu. My machine has Ubuntu 20.04. The CI image you refer to is Ubuntu 18.04. What exactly has been changed in the CI image I do not understand.)

I have just run the test directories that fail in the CI. All of them are successful for me. I have attached the result here. I added .log to the filename, because .html is not allowed.

Does this help or can you tell me what I would do better?

index.html.log

[HarelM]

It will be solved by #1003 in any case...