[FIX] sap.m.CheckBox: DisplayOnly icon size aligned with specification
[FIX] sap.m.CheckBox: DisplayOnly icon size aligned with specification

BCP: 1970369576

Change-Id: I183fda766645685920852eec277263bbdecaa375

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