QFontDatabase Amharic support

Hi,

QFontDatabase::families() reports that I have the Ebrima font on my system, which supports Amharic characters.

However my application does not display these kind of characters (replaced with blank characters instead), and QFontDatabase::families() does not have an enum equivalent to QChar::Script_Ethiopic so I can't check if the family is the problem.

https://doc-snapshots.qt.io/qt6-dev/qfontdatabase.html#WritingSystem-enum

QFontDatabase documentation seems to imply that there will be a lookup to find an appropriate system font if a text is not supported by the main font.