Change default font-face to Noto Sans Regular [#311]

[bdon]

• Change it from Open Sans Regular, Arial Unicode MS Regular which does not have a freely licensed reproducible build.

See #311 for discussion.

I don't think that this change is high priority, I'd be fine with keeping the current defaults indefinitely. The consensus seems to be that this default should nearly never be used anyways.

Launch Checklist

• Confirm your changes do not include backports from Mapbox projects (unless with compliant license) - if you are not sure about this, please ask!
• Briefly describe the changes in this PR.
• Link to related issues.
• Document any changes to public APIs.
• Add an entry to CHANGELOG.md under the ## main section.

[HarelM]

I need to fix CI... sorry.
What about introducing the global default instead of this implicit default?

[bdon]

While I think that is a better solution, it introduce a new feature to the style, which I find undesirable, and can accomplish it using a preprocessor anyways.

[wipfli]

Thanks @bdon for opening this pull request.

This looks like a breaking change in the style specification and I think breaking changes here should be avoided.

Maybe one day in the future we can make a "New MapLibre Style Spec" and have a bunch of breaking changes there, but until then I would say let's avoid breaking changes.

So I would say let's not merge this one...

[bdon]

OK, sounds good to me. Thanks for reviewing.