Need ability to add more than one yamcs instance per one openmct instantiation

[haisamido]

Is your feature request related to a problem? Please describe.
Need ability to add more than one yamcs instance per one openmct instantiation, because we have one yamcs server, a mission, with multiple defined instances, i.e.spacecraft.

Describe the solution you'd like
This configuration

const config = {
    yamcsDictionaryEndpoint: "http://localhost:9000/yamcs-proxy/",
    yamcsHistoricalEndpoint: "http://localhost:9000/yamcs-proxy/",
    yamcsWebsocketEndpoint: "ws://localhost:9000/yamcs-proxy-ws/",
    yamcsUserEndpoint: "http://localhost:9000/yamcs-proxy/api/user/",
    yamcsInstance: "myproject",
    yamcsProcessor: "realtime",
    yamcsFolder: "myproject",
    throttleRate: 1000,

should be more like:

const config = {
    yamcsDictionaryEndpoint: "http://localhost:9000/yamcs-proxy/",
    yamcsHistoricalEndpoint: "http://localhost:9000/yamcs-proxy/",
    yamcsWebsocketEndpoint: "ws://localhost:9000/yamcs-proxy-ws/",
    yamcsUserEndpoint: "http://localhost:9000/yamcs-proxy/api/user/",
    yamcsInstances: ["myproject1","myproject2"]
    yamcsProcessor: "realtime",
    yamcsFolders: ["myproject1","myproject2"]
    throttleRate: 1000,

in order for the HTML UI to display parameters from each instance (spacecraft) in a drop down list

Describe alternatives you've considered
Having more than one openmct running which is not ideal for a mission that has multiple spacecraft.

Additional context
TBD