update documentdb index.d.ts
update documentdb index.d.ts

update documentdb index.d.ts to patch _ts type from string to number
AgentME/DefinitelyTyped,one-pieces/DefinitelyTyped,alexdresko/DefinitelyTyped,zuzusik/DefinitelyTyped,rolandzwaga/DefinitelyTyped,georgemarshall/DefinitelyTyped,arusakov/DefinitelyTyped,AgentME/DefinitelyTyped,arusakov/DefinitelyTyped,mcliment/DefinitelyTyped,dsebastien/DefinitelyTyped,alexdresko/DefinitelyTyped,magny/DefinitelyTyped,chrootsu/DefinitelyTyped,georgemarshall/DefinitelyTyped,rolandzwaga/DefinitelyTyped,laurentiustamate94/DefinitelyTyped,chrootsu/DefinitelyTyped,markogresak/DefinitelyTyped,georgemarshall/DefinitelyTyped,dsebastien/DefinitelyTyped,arusakov/DefinitelyTyped,zuzusik/DefinitelyTyped,AgentME/DefinitelyTyped,borisyankov/DefinitelyTyped,georgemarshall/DefinitelyTyped,AgentME/DefinitelyTyped,borisyankov/DefinitelyTyped,zuzusik/DefinitelyTyped,magny/DefinitelyTyped