[INTERNAL][FIX] sap.m.CheckBox: Fixed label positioning
[INTERNAL][FIX] sap.m.CheckBox: Fixed label positioning

Problem:
When sap.m.CheckBox is placed in the overflow popover of sap.m.OverflowToolbar as last child, scroll bar appears.

BCP: N/A
Change-Id: I84a9fa3bd7ce60cb7b177739c10efb6e38814e80

SAP/openui5,SAP/openui5,SAP/openui5,SAP/openui5