Add discord-rpc missing Presence typings (#38965)
Add discord-rpc missing Presence typings (#38965)

* Added missing properties

Some properties remained missing so here are the up-to-date ones. For reference [this](https://github.com/discordapp/discord-api-docs/blob/master/docs/rich_presence/How_To.md#update-presence-payload-fields) is where they're all defined.
Added:
 - instance?: boolean;
 - partySize?: number;
 - partyMax?: number;
 - matchSecret?: string;
 - spectateSecret?: string;
 - joinSecret?: string;
  - instance?: number;

* Converted spaces to tabs (linted)

* Removed duplicate instance

georgemarshall/DefinitelyTyped,mcliment/DefinitelyTyped,dsebastien/DefinitelyTyped,georgemarshall/DefinitelyTyped,georgemarshall/DefinitelyTyped,georgemarshall/DefinitelyTyped,markogresak/DefinitelyTyped,dsebastien/DefinitelyTyped