Fix linter errors on react native 0.74

[ipoogleduck]

Removes this error:

/Users/xxx/Documents/GitHub/xxx/node_modules/react-native-calendar-events/android/src/main
/java/com/calendarevents/RNCalendarEvents.java:1090: Error: Value must be ≥ 0 but getColumnIndex can be -1 [Ra
nge]
            if (cursor.getColumnIndex(CalendarContract.Events.DURATION) != -1 && cursor.getString(cursor.getCo
lumnIndex(CalendarContract.Events.DURATION)) != null) {