[FIX] CONTRIBUTING.md Dead link fixed
[FIX] CONTRIBUTING.md Dead link fixed

Fix broken url to the Corporate Contributor License Agreement in the
CONTRIBUTING.md

Closes https://github.com/SAP/openui5/pull/1498

Change-Id: Iae04a4aad2cfad00d73e5b9c75d3c43fa2bb94d5

SAP/openui5,nzamani/openui5,SAP/openui5,SQCLabs/openui5,cschuff/openui5,SQCLabs/openui5,SAP/openui5,nzamani/openui5,nzamani/openui5,cschuff/openui5,SQCLabs/openui5,SAP/openui5,cschuff/openui5