fix #307075 : Bold and underlined text is not displayed properly unde…

[AntonioBL]

…r Windows and Linux

Resolves: https://musescore.org/en/node/307075

The workaround of eb33bfa83 introduced a side effect for texts when they are bold and underlined at the same time.
This PR reverts to the previous behavior for this particular case. This means that for some particular fonts, when the texts are at the same time bold and underlined, bug https://musescore.org/en/node/284218 will appear again (as in MuseScore 3.4.2). For Windows and Linux.

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