feat(interview-scheduler): add new endpoints & update the schema

[cagdas001]

• Update Interview schema with new additions & changes.
  • Add xaiId column.
  • Add rescheduleUrl column.
  • Add endTimestamp column.
  • Add duration column.
  • Add templateId column.
  • Add templateType column.
  • Add title column.
  • Add locationDetails column.
  • Add hostName column.
  • Add hostEmail column.
  • Add guestNames column.
  • Rename column attendeesList to guestEmails
  • Rename column googleCalendarId to calendarEventId
  • Rename column xaiTemplate to templateUrl
  • Remove customMessage column
• Update the interviews in demo data based on schema changes.
• Add migrations/2021-05-09-interviews-table-migration.js migration for schema changes.
• Add GET /getInterview/:id endpoint.
• Add PATCH /updateInterview/:id endpoint.
• Update the POSTMAN collection & environment for new endpoints & schema changes.
• Update the Swagger for new endpoints & schema changes.