fix(code-block): fix local-storage breakage

[zchsh]

🎟️ Asana Task
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Description

This PR fixes an issue where code-block could cause app breakage by trying to access window.localStorage without first confirming that window.localStorage is available.

window.localStorage is not available if the visitor has blocked all cookies.

I've proven out this change in hashicorp/dev-portal#1147.

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🦋 Changeset detected

Latest commit: cbfefc0

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

This PR includes changesets to release 1 package

Name	Type
@hashicorp/react-code-block	Patch

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Name	Status	Preview	Updated
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📦 Canary Packages Published

Latest commit: cbfefc0

Published 2 packages

@hashicorp/react-code-block@6.1.1-canary-20221003145352

npm install @hashicorp/react-code-block@canary

@hashicorp/react-intro@0.4.2-canary-20221003145352

npm install @hashicorp/react-intro@canary

[zchsh]

Added this utility function to try to keep the provider code simple, while handling the case where window.localStorage is not available.

[zchsh]

@BRKalow This fix targets the localStorage issue described in 🎟️ App breaks when local storage is disabled. I've tested this pre-release in hashicorp/dev-portal#1147, so I'm fairly confident it's at least on the right track (thanks for the code-block tip in the Asana task!)

Let me know what you think 🙇