Fixes #447

Problem

• MeetingClient.getParticipant requires tenantId to be a url param
• URL params need encoding

Fix

1. Add tenantId to getParticipant as third parameter and add it as url parameter ?tenantId=${tenantId}
2. Update getParticipant and getById with URI encoding
3. Update tests
4. Docs updates TBD in teams.sdk