Function getLeapMonth

getLeapMonth(year): number
Return the lunar leap month in the year otherwise return 0
Parameters
- year: number
  lunar year
Returns number
Leap month in a lunar year
Example
```
// => 3
getLeapMonth(2023)
```
Example
```
// => 0
getLeapMonth(2024)
```
- Defined in src/get-leap-month/index.ts:16