[feature](function) support ngram_search function #38226

[Mryange]

#38226
mysql [test]>select ngram_search('123456789' , '12345' , 3); +---------------------------------------+
| ngram_search('123456789', '12345', 3) |
+---------------------------------------+
| 0.6 |
+---------------------------------------+
1 row in set (0.01 sec)

mysql [test]>select ngram_search("abababab","babababa",2); +-----------------------------------------+
| ngram_search('abababab', 'babababa', 2) |
+-----------------------------------------+
| 1 |
+-----------------------------------------+
1 row in set (0.01 sec)

doc https://github.com/apache/doris-website/pull/899
## Proposed changes
Issue Number: close #xxx
<!--Describe your changes.-->

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[Mryange]

run buildall

[github-actions]

clang-tidy review says "All clean, LGTM! 👍"

[Mryange]

run buildall

[github-actions]

clang-tidy review says "All clean, LGTM! 👍"

[doris-robot]

TeamCity be ut coverage result:
Function Coverage: 36.15% (9329/25804)
Line Coverage: 27.72% (76644/276527)
Region Coverage: 26.50% (39351/148516)
Branch Coverage: 23.29% (20036/86016)
Coverage Report: http://coverage.selectdb-in.cc/coverage/52188cd34ffa103e17edd85a1446e92d7913cb7e_52188cd34ffa103e17edd85a1446e92d7913cb7e/report/index.html

[Mryange]

run buildall

[github-actions]

clang-tidy review says "All clean, LGTM! 👍"

[doris-robot]

TeamCity be ut coverage result:
Function Coverage: 36.16% (9331/25804)
Line Coverage: 27.72% (76663/276527)
Region Coverage: 26.51% (39369/148516)
Branch Coverage: 23.30% (20046/86016)
Coverage Report: http://coverage.selectdb-in.cc/coverage/8637ca9d7c95d30d2b9bbac2ca1ce2c0bbcf650c_8637ca9d7c95d30d2b9bbac2ca1ce2c0bbcf650c/report/index.html