### What changes were proposed in this pull request?
Extend `YearMonthIntervalType` to support interval fields. Valid interval field values:
- 0 (YEAR)
- 1 (MONTH)
After the changes, the following year-month interval types are supported:
1. `YearMonthIntervalType(0, 0)` or `YearMonthIntervalType(YEAR, YEAR)`
2. `YearMonthIntervalType(0, 1)` or `YearMonthIntervalType(YEAR, MONTH)`. **It is the default one**.
3. `YearMonthIntervalType(1, 1)` or `YearMonthIntervalType(MONTH, MONTH)`
Closes#32825
### Why are the changes needed?
In the current implementation, Spark supports only `interval year to month` but the SQL standard allows to specify the start and end fields. The changes will allow to follow ANSI SQL standard more precisely.
### Does this PR introduce _any_ user-facing change?
Yes but `YearMonthIntervalType` has not been released yet.
### How was this patch tested?
By existing test suites.
Closes#32909 from MaxGekk/add-fields-to-YearMonthIntervalType.
Authored-by: Max Gekk <max.gekk@gmail.com>
Signed-off-by: Max Gekk <max.gekk@gmail.com>
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