eeschema: fix issue: Moving a hierarchical pin slightly move also other hierarchical pins

Fixes: lp:1808687
https://bugs.launchpad.net/kicad/+bug/1808687

eeschema/sch_painter.cpp

@@ -1272,20 +1272,25 @@ void SCH_PAINTER::draw( SCH_SHEET *aSheet, int aLayer )
         {
             if( !sheetPin.IsMoving() )
             {
+                // For aesthetic reasons, the SHEET_PIN is drawn with a small offset
+                // of width / 2
                 int width = aSheet->GetPenSize();
-                wxPoint pt = sheetPin.GetTextPos();
+                wxPoint initial_pos = sheetPin.GetTextPos();
+                wxPoint offset_pos = initial_pos;
 
                 switch( sheetPin.GetEdge() )
                 {
-                case SCH_SHEET_PIN::SHEET_TOP_SIDE:    pt.y -= width / 2; break;
-                case SCH_SHEET_PIN::SHEET_BOTTOM_SIDE: pt.y += width / 2; break;
-                case SCH_SHEET_PIN::SHEET_RIGHT_SIDE:  pt.x -= width / 2; break;
-                case SCH_SHEET_PIN::SHEET_LEFT_SIDE:   pt.x += width / 2; break;
+                case SCH_SHEET_PIN::SHEET_TOP_SIDE:    offset_pos.y -= width / 2; break;
+                case SCH_SHEET_PIN::SHEET_BOTTOM_SIDE: offset_pos.y += width / 2; break;
+                case SCH_SHEET_PIN::SHEET_RIGHT_SIDE:  offset_pos.x -= width / 2; break;
+                case SCH_SHEET_PIN::SHEET_LEFT_SIDE:   offset_pos.x += width / 2; break;
                 default: break;
                 }
 
-                sheetPin.SetTextPos(pt);
+                sheetPin.SetTextPos( offset_pos );
                 draw( static_cast<SCH_HIERLABEL*>( &sheetPin ), aLayer );
+                m_gal->DrawLine( offset_pos, initial_pos );
+                sheetPin.SetTextPos( initial_pos );
             }
         }
     }