### What changes were proposed in this pull request?
A java like string trim method trims all whitespaces that less or equal than 0x20. currently, our UTF8String handle the space =0x20 ONLY. This is not suitable for many cases in Spark, like trim for interval strings, date, timestamps, PostgreSQL like cast string to boolean.
### Why are the changes needed?
improve the white spaces handling in UTF8String, also with some bugs fixed
### Does this PR introduce any user-facing change?
yes,
string with `control character` at either end can be convert to date/timestamp and interval now
### How was this patch tested?
add ut
Closes#26626 from yaooqinn/SPARK-29986.
Authored-by: Kent Yao <yaooqinn@hotmail.com>
Signed-off-by: Wenchen Fan <wenchen@databricks.com>
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