Don't show grips on brackets on single click

Currently this leads to a crash on trying to adjust bracket column
in Inspector so revert this change for now.

Author: dmitrio95

libmscore/bracket.h

@@ -97,7 +97,6 @@ class Bracket final : public Element {
       void undoChangeProperty(Pid id, const QVariant& v, PropertyFlags ps) override;
       using ScoreElement::undoChangeProperty;
 
-      Element::EditBehavior normalModeEditBehavior() const override { return Element::EditBehavior::Edit; }
       int gripsCount() const override { return 1; }
       Grip initialEditModeGrip() const override { return Grip::START; }
       Grip defaultGrip() const override { return Grip::START; }