fixes match statements to work with PositionProvider

[imsut]

Summary

(This is a rebase of #1369)

Fixes #1322 where PositionProvider does not provide positions for whitespace. The issue seems to be that when there is no pattern for whitespace nodes during codegen, then they are not included in the position metadata.

Test Plan

• Added a test
• Verified this test failed
• Implemented fix and verified fix

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[drinkmorewaterr]

Thanks for doing this! 😁
LGTM, will merge once CI comes back green !

[imsut]

@drinkmorewaterr -- I'd like to try this fix. Is there a plan to cut a release v1.8.3?