[INTERNAL] sap.m.CheckBox: Improve JSDoc
[INTERNAL] sap.m.CheckBox: Improve JSDoc

The JSDoc annotations are improved for better TypeScript support.

JIRA: BGSOFUIPIRIN-5939
Change-Id: I28adb44bb412c725e6606c3fef9c562e0a5f0f72

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