TextEditor: Replace 'Monaco' with 'Menlo' on macOS

According to https://en.wikipedia.org/wiki/Menlo_(typeface) 'Menlo' is
the newer font family.

Is also in sync with the font used by the Terminal plugin.

Task-number: QTCREATORBUG-29964
Change-Id: I50b439be32f08176b910017b68384ea61cab7337
Reviewed-by: Tor Arne Vestbø <tor.arne.vestbo@qt.io>

src/plugins/texteditor/fontsettings.cpp

@@ -487,7 +487,7 @@ void FontSettings::setColorScheme(const ColorScheme &scheme)
 static QString defaultFontFamily()
 {
     if (Utils::HostOsInfo::isMacHost())
-        return QLatin1String("Monaco");
+        return QLatin1String("Menlo");
 
     const QString sourceCodePro(g_sourceCodePro);
     const QFontDatabase dataBase;