code correction for type flow: Correct path build for windows

[madhurisandbhor]

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TODO:

• [x] Update CHANGELOG.md* with your change (include reference to issue & this PR)
• [x] Make sure all of the significant new logic is covered by tests
• [x] Rebase your changes on master so that they can be merged easily
• [x] Make sure all tests and linter rules pass

*Make sure changelog entries note which project(s) has been affected. See older entries for examples on what this looks like.

[apollo-cla]

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