fix: Ensure getting git branch doesn't fail on Windows

[sidharthachatterjee]

Fixes #900

[changeset-bot]

🦋 Changeset detected

Latest commit: 0ea5fb7

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
wrangler	Patch

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[github-actions]

A wrangler prerelease is available for testing. You can install this latest build in your project with:

npm install --save-dev https://prerelease-registry.developers.workers.dev/runs/2282969451/npm-package-wrangler-914

You can reference the automatically updated head of this PR with:

npm install --save-dev https://prerelease-registry.developers.workers.dev/prs/914/npm-package-wrangler-914

Or you can use npx with this latest build directly:

npx https://prerelease-registry.developers.workers.dev/runs/2282969451/npm-package-wrangler-914 dev path/to/script.js

[threepointone]

Do you have any tests for this?

[sidharthachatterjee]

@threepointone Unfortunately not at the moment. We'll need to do this "properly" after launch.

[CEbbinghaus]

Love to see it thanks 👍