fix invalid value for offset_join_style in main options

Author: 3nids

src/app/qgsoptions.cpp

@@ -937,7 +937,7 @@ QgsOptions::QgsOptions( QWidget *parent, Qt::WindowFlags fl, const QList<QgsOpti
   mOffsetJoinStyleComboBox->addItem( tr( "Round" ), 0 );
   mOffsetJoinStyleComboBox->addItem( tr( "Miter" ), 1 );
   mOffsetJoinStyleComboBox->addItem( tr( "Bevel" ), 2 );
-  mOffsetJoinStyleComboBox->setCurrentIndex( mSettings->value( QStringLiteral( "/qgis/digitizing/offset_join_style" ), 0 ).toInt() );
+  mOffsetJoinStyleComboBox->setCurrentIndex( mSettings->value( QStringLiteral( "/qgis/digitizing/offset_join_style" ), QgsGeometry::JoinStyleRound ).toInt() );
   mOffsetQuadSegSpinBox->setValue( mSettings->value( QStringLiteral( "/qgis/digitizing/offset_quad_seg" ), 8 ).toInt() );
   mCurveOffsetMiterLimitComboBox->setValue( mSettings->value( QStringLiteral( "/qgis/digitizing/offset_miter_limit" ), 5.0 ).toDouble() );