Add optional parameters to RUM snippets

[kimsauce]

Service is the only parameter shown in RUM snippets because it's mandatory (rest are optional).

We can add application and environment to make it more complete, but we should do that in all places, including https://github.com/SumoLogic/sumologic-opentelemetry-js and all methods (Synchronous, Asynchronous, NPM). If you have the time for that - go ahead and please work with dev team.

Originally posted by @pbrzoska-sumo in https://github.com/SumoLogic/sumologic-documentation/pull/1414#discussion_r1085515997