[Scheduling Tool] Limit the number of meetings teams can schedule

We started to see that some of the teams using the scheduling tool are scheduling many meetings in advance. Some even scheduling 1 meeting every week for a full month. Often these are just place holders in case the team is ready to meet with the arch board at that time but often end up getting rescheduled or cancelled. I propose we limit the number of meetings a team can schedule to at most 2 upcoming meetings. This way teams cannot fill up the calendar with place holder meetings.

@kyle-patterson @ladonnaq @maririos

The issue names only the scheduling tool and no files, tests, or entry points. Start by locating the tool's meeting-scheduling flow and confirm how “team” and “upcoming” are defined; done means a team cannot have more than two upcoming meetings and the behavior is covered by the relevant tests.

Written by the indexing model from the issue text.