getCalendarListEntry loads how one accessible calendar appears for the
connected user, including colors, visibility, reminders, and notifications.
Example
Inputs
calendar: string is required. account optionally selects the Google account.
Output
Returns aCalendar including list-specific backgroundColor,
foregroundColor, colorId, hidden, selected, summaryOverride,
defaultReminders, notifications, accessRole, primary, and deleted, in
addition to the metadata described by Get calendar.