style: sentence case texts across documentation

[tobySolutions]

Why?

This pull request helps to sentence-case the headers across the documentation. It also fixes a scroll bug I noticed on the documentation.

Tickets?

• Sentence case headers, buttons, sidebar links and in-page links throughout /docs

Contribution checklist?

• The commit messages are detailed
• The build command runs locally
• Assets or static content are linked and stored in the project
• Document filename is named after the slug
• You've reviewed spelling using a grammar checker
• For documentation, guides or references, you've tested the commands and steps
• You've done enough research before writing

Security checklist?

• Sensitive data has been identified and is being protected properly
• Injection has been prevented (parameterized queries, no eval or system calls)
• The Components are escaping output (to prevent XSS)

[changeset-bot]

⚠️ No Changeset found

Latest commit: 57afa19

Merging this PR will not cause a version bump for any packages. If these changes should not result in a new version, you're good to go. If these changes should result in a version bump, you need to add a changeset.

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[nlc616]

LGTM