[bugfix] find key by prefix, append ':' into prefix
[bugfix] find key by prefix, append ':' into prefix

CNSRE/ABTestingGateway,nashuiliang/ABTestingGateway,nashuiliang/ABTestingGateway,nashuiliang/ABTestingGateway,CNSRE/ABTestingGateway,SinaMSRE/ABTestingGateway,CNSRE/ABTestingGateway,nashuiliang/ABTestingGateway,CNSRE/ABTestingGateway