UI: Remove button box setIcon

Since these are now set in the stylesheets, these lines are not
needed anymore.

UI/window-basic-settings.cpp

@@ -912,10 +912,6 @@ OBSBasicSettings::OBSBasicSettings(QWidget *parent)
 		SLOT(AdvOutRecCheckWarnings()));
 	AdvOutRecCheckWarnings();
 
-	ui->buttonBox->button(QDialogButtonBox::Apply)->setIcon(QIcon());
-	ui->buttonBox->button(QDialogButtonBox::Ok)->setIcon(QIcon());
-	ui->buttonBox->button(QDialogButtonBox::Cancel)->setIcon(QIcon());
-
 	SimpleRecordingQualityChanged();
 	AdvOutSplitFileChanged();