Function isLastDayOfMonth

isLastDayOfMonth(date?: Date): boolean
Returns whether the given date is the last day of month
Parameters
- Optionaldate: Date
  the date to check
Returns boolean
whether the date is the last day of month
Author
David Hsing
Example
```
isLastDayOfMonth(new Date(2023, 8, 1));    // false
isLastDayOfMonth(new Date(2023, 8, 30));    // true
```