fix(docs-page): make certain docs-page types optional

[BRKalow]

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Description

showEditPage, showVersionSelect, and additionalComponents are not necessary to be specified for every usage, making them optional!

PR Checklist 🚀

Items in this checklist may not may not apply to your PR, but please consider each item carefully.

• Add Asana and Preview links above.
• Conduct thorough self-review.
• Add or update tests as appropriate.
• Conduct reasonable cross browser testing for both compatibility and responsive behavior (We have a Sauce Labs account for this, if you don't have access, just ask!).
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• Identify (in the description above) and document (add Asana tasks on this board) any technical debt that you're aware of, but are not addressing as part of this PR.

[changeset-bot]

🦋 Changeset detected

Latest commit: 6bf598f

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-docs-page	Patch

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[thiskevinwang]

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