This allows license checking tools to omit the OFL and UFL licenses when
`default_fonts` are turned off.
There was some discussion of versioning on the original issue; I have
chosen to label this version as `0.28.1` to match the other crates.
Happy to adjust the version as needed.
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* Closes <https://github.com/emilk/egui/issues/2321>
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---------
Co-authored-by: Alex Pinkus <pinkus@amazon.com>
