Portfolio Plan API: Expose Teams instead of Plan Teams

Summary

Currently the get plan endpoint "/jira/rest/jpo-api/1.0/plan" returns a plan with a list of PlanTeam IDs. We should instead be giving a list of Team IDs. Otherwise a user won't be able to do basic things like, what are the names of the teams in my plan.

Workaround

1. Send a GET request using /rest/teams-api/1.0/team to get the full list of teams
2. Send a POST request using /rest/jpo/1.0/team/get and this JSON body:

   {
   	// ID of the plan
   	"planId"     : 1,
   	
   	// If scenario teams are wanted, the scenarioId can be provided here. Otherwise just use -1
   	"scenarioId" : -1,
   	
   	// This should be the full list of teams returned by /rest/teams-api/1.0/team, formatted as strings
   	"itemKeys"   : [
   		"4",
   		"7",
   		"14"
   		// ...etc
   	]
   }
   

The rest endpoint will then return info related to those teams. You will then need to filter out all teams that have "isPlanTeam" value of false. The remaining teams are the ones that belong in the plan.