Do not keep highlight when locking/unlocking feature

It was a bit strange effect when locking feature... when moving mouse
over a feature it would have highlight, then on right click it would
also get vertex editor square markers in addition to the highlight, but
then immediately after mouse move the original highlight would be gone.
Now it's simplified so that feature highlight on right click gets removed.

(cherry picked from commit 6fd21c2)

Author: wonder-sk

src/app/vertextool/qgsvertextool.cpp

@@ -959,7 +959,6 @@ void QgsVertexTool::tryToSelectFeature( QgsMapMouseEvent *e )
     // we have a feature to select
     QPair<QgsVectorLayer *, QgsFeatureId> alternative = mSelectedFeatureAlternatives->alternatives.at( mSelectedFeatureAlternatives->index );
     updateVertexEditor( alternative.first, alternative.second );
-    updateFeatureBand( QgsPointLocator::Match( QgsPointLocator::Area, alternative.first, alternative.second, 0, QgsPointXY() ) );
   }
   else
   {
@@ -970,8 +969,11 @@ void QgsVertexTool::tryToSelectFeature( QgsMapMouseEvent *e )
     {
       mVertexEditor->updateEditor( nullptr );
     }
-    updateFeatureBand( QgsPointLocator::Match() );
   }
+
+  // we have either locked ourselves to a feature or unlocked again
+  // in any case, we don't want feature highlight anymore (vertex editor has its own highlight)
+  updateFeatureBand( QgsPointLocator::Match() );
 }