[INTERNAL][FIX] BlockBase: JSDoc typo for showSubSectionMore is fixed
[INTERNAL][FIX] BlockBase: JSDoc typo for showSubSectionMore is fixed

JSDoc typo for showSubSectionMore property is fixed and now the
documentation in DemoKit is visualized correctly.

Change-Id: I5a27ceee6650fb15b2170d3df293737ea75fd6f2
BCP: 1880518167

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