Adding master_event_id as a property to the Event data class (#241)

# Description

Adding getter/setter support for `master_even_id`

# License
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src/main/kotlin/com/nylas/models/Event.kt

@@ -93,6 +93,11 @@ data class Event(
    */
   @Json(name = "organizer")
   val organizer: EmailName? = null,
+  /**
+   * Organizer of the event.
+   */
+  @Json(name = "master_event_id")
+  val masterEventId: String? = null,
   /**
    * A list of RRULE and EXDATE strings.
    * @see <a href="https://datatracker.ietf.org/doc/html/rfc5545#section-3.8.5">RFC-5545</a>