LibGfx: Missing ring in 'Å' glyph in Gothia Serif

[awesomekling]

See attached test case.

test.zip

Firefox:

Ladybird:

[janso3]

I think the issue here is what I wanted to fix in https://github.com/SerenityOS/serenity/pull/17934, but I ran into an issue with subpixel positioning at low sizes. Basically, we allocate a glyph bitmap for the area between ascender and descender, but outlines may actually go from ymax to ymin.