[DEV-3092] Fix layout of guide's menu and guide's content

[Sebastiano-Bertolin]

List of Changes

Include h3 heading level in guide in page menu rendering
Adjust padding for heading in Guide contend and for section and items in the left menu
Adjust font size and weight for right in guide menu

Motivation and Context

How Has This Been Tested?

Screenshots (if appropriate):

Types of changes

• Chore (nothing changes by a user perspective)
• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly.

[changeset-bot]

🦋 Changeset detected

Latest commit: 0f482a4

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

This PR includes changesets to release 2 packages

Name	Type
nextjs-website	Minor
gitbook-docs	Minor

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[github-actions]

Branch is not up to date with base branch

@Sebastiano-Bertolin it seems this Pull Request is not updated with base branch.
Please proceed with a merge or rebase to solve this.

[github-actions]

Jira Pull Request Link

This Pull Request refers to the following Jira issue DEV-3092