Support array indexing for duckdb

[JichaoS]

https://duckdb.org/docs/sql/data_types/list#retrieving-from-lists

[coveralls]

Pull Request Test Coverage Report for Build 8993828008

Details

• 16 of 17 (94.12%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.003%) to 89.215%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
tests/sqlparser_duckdb.rs	15	16	93.75%

Totals
Change from base Build 8989250736:	0.003%
Covered Lines:	24443
Relevant Lines:	27398

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💛 - Coveralls

[jmhain]

lgtm, thanks! cc @alamb

[alamb]

Thanks @JichaoS and @jmhain