Accept WINDOW clause after QUALIFY when parsing

[iffyio]

The positioning of QUALIFY and WINDOW clauses differ between dialects.
BigQuery requires that WINDOW clauses come after QUALIFY which fails on the parser as a result.
This updates the parser to accept the clauses in either order.
It's also possible to flag this behavior on the dialect level so that we don't parse one for the other (didn't opt for that in this case because it felt like a minor detail but probably make more sense), let me know if that's preferred! Actually found some dialects like databricks can accept either order so probably makes sense to have the parser accept in any order

[coveralls]

Pull Request Test Coverage Report for Build 8678974573

Details

• 26 of 28 (92.86%) changed or added relevant lines in 3 files are covered.
• 2 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-0.007%) to 88.082%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/parser/mod.rs	12	14	85.71%

Files with Coverage Reduction	New Missed Lines	%
src/parser/mod.rs	2	82.97%

Totals
Change from base Build 8660968190:	-0.007%
Covered Lines:	21299
Relevant Lines:	24181

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💛 - Coveralls

[alamb]

Looks good to me -- thanks @iffyio

[alamb]

This branch has conflicts so I couldn't merge it directly. Instead i made #1248 with the same commit