Updated pkg to most recent version and updated Windows contributing instructions

[ShadowCat567]

Description of changes

Updated Windows CONTRIBUTING.md instructions and updated pkg-fetch. pkg-fetch was creating windows build issues in its current form. Workarounds related to pkg-fetch, no longer needed. Fixed error in precommit hook for Windows if no files included in commit that match js/tsx extensions were modified.

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• [x] PR description included
• [ ] yarn test passes
• [ ] Tests are changed or added
• [x] Relevant documentation is changed or added (and PR referenced)
• [ ] Pull request labels are added

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