feat: add duckdb "INSTALL" and "LOAD"

[universalmind303]

adds support for parsing duckdbs extension syntax. INSTALL [extension] and LOAD [extension]

[alamb]

Looks good to me -- thank you @universalmind303

[coveralls]

Pull Request Test Coverage Report for Build 7838351892

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A quick fix for this PR: rebase it; your next report should be accurate.

• -2 of 30 (93.33%) changed or added relevant lines in 3 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.007%) to 87.672%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/ast/mod.rs	4	6	66.67%

Totals
Change from base Build 7838299826:	0.007%
Covered Lines:	19600
Relevant Lines:	22356

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💛 - Coveralls

[alamb]

I merged up from main to pick up #1130 and make some small fixes to get CI to pass (as I had it downloaded anyways)