### What changes were proposed in this pull request?
Add typeof function for Spark to get the underlying type of value.
```sql
-- !query 0
select typeof(1)
-- !query 0 schema
struct<typeof(1):string>
-- !query 0 output
int
-- !query 1
select typeof(1.2)
-- !query 1 schema
struct<typeof(1.2):string>
-- !query 1 output
decimal(2,1)
-- !query 2
select typeof(array(1, 2))
-- !query 2 schema
struct<typeof(array(1, 2)):string>
-- !query 2 output
array<int>
-- !query 3
select typeof(a) from (values (1), (2), (3.1)) t(a)
-- !query 3 schema
struct<typeof(a):string>
-- !query 3 output
decimal(11,1)
decimal(11,1)
decimal(11,1)
```
##### presto
```sql
presto> select typeof(array[1]);
_col0
----------------
array(integer)
(1 row)
```
##### PostgreSQL
```sql
postgres=# select pg_typeof(a) from (values (1), (2), (3.0)) t(a);
pg_typeof
-----------
numeric
numeric
numeric
(3 rows)
```
##### impala
https://issues.apache.org/jira/browse/IMPALA-1597
### Why are the changes needed?
a function which is better we have to help us debug, test, develop ...
### Does this PR introduce any user-facing change?
add a new function
### How was this patch tested?
add ut and example
Closes#26599 from yaooqinn/SPARK-29961.
Authored-by: Kent Yao <yaooqinn@hotmail.com>
Signed-off-by: HyukjinKwon <gurwls223@apache.org>
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