fix: wrangler init should not crash if Git is not available on Windows

[petebacondarwin]

We check for the presence of Git by trying to run git --version.
On non-Windows we get an Error with code set to "ENOENT".
One Windows we get a different error:

{
  "shortMessage":"Command failed with exit code 1: git --version",
  "command":"git --version",
  "escapedCommand":"git --version",
  "exitCode":1,
  "stdout":"",
  "stderr":"'git' is not recognized as an internal or external command,\r\noperable program or batch file.",
  "failed":true,
  "timedOut":false,
  "isCanceled":false,
  "killed":false
}

Since we don't really care what the error is, now we just assume that Git
is not available if an error is thrown.

Fixes #1022

[changeset-bot]

🦋 Changeset detected

Latest commit: bb2d1d8

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/2334328048/npm-package-wrangler-1033

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

npm install --save-dev https://prerelease-registry.developers.workers.dev/prs/1033/npm-package-wrangler-1033

Or you can use npx with this latest build directly:

npx https://prerelease-registry.developers.workers.dev/runs/2334328048/npm-package-wrangler-1033 dev path/to/script.js

[threepointone]

Thank you for investigating and fixing!