docs: Update hot-design-getstarted-guide.md

[sasakrsmanovic]

Added a remark that you must have the beta access. .

GitHub Issue (If applicable): closes #

PR Type

• Documentation content changes

What kind of change does this PR introduce?

What is the current behavior?

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Please check if your PR fulfills the following requirements:

• Docs have been added/updated which fit documentation template (for bug fixes / features)
• Unit Tests and/or UI Tests for the changes have been added (for bug fixes / features) (if applicable)
• Validated PR Screenshots Compare Test Run results.
• Contains NO breaking changes
• Associated with an issue (GitHub or internal) and uses the automatic close keywords.
• Commits must be following the Conventional Commits specification.

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Internal Issue (If applicable):

[unodevops]

⚠️⚠️ The build 150712 has failed on Uno.UI - docs.

[morning4coffe-dev]

Looks good, just updated the PR to follow conventional commits.

[morning4coffe-dev]

https://github.com/Mergifyio backport release/stable/5.5

[mergify]

backport release/stable/5.5

✅ Backports have been created

• #19115 docs: Update hot-design-getstarted-guide.md (backport #19114) has been created for branch release/stable/5.5

[unodevops]

🤖 Your Docs stage site is ready! Visit it here: https://unodocsprstaging.z13.web.core.windows.net/pr-19114/index.html