Removed code backticks from <kbd> blocks

[jnidzwetzki]

Why:

Closes #19064

What's being changed (if available, include any code snippets, screenshots, or gifs):

The unnecessary code backticks around <kbd> blocks are removed.

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• I have reviewed my changes in staging (look for the "Automatically generated comment" and click the links in the "Preview" column to view your latest changes).
• For content changes, I have completed the self-review checklist.

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• This pull request impacts the contribution experience
  • I have added the 'writer impact' label
  • I have added a description and/or a video demo of the changes below (e.g. a "before and after video")

[welcome]

Thanks for opening this pull request! A GitHub docs team member should be by to give feedback soon. In the meantime, please check out the contributing guidelines.

[github-actions]

👋 Hey there spelunker. It looks like you've modified some files that we can't accept as contributions. The complete list of files we can't accept are:
.devcontainer/**
.github/actions-scripts/**
.github/workflows/**
.github/CODEOWNERS
assets/fonts/**
data/graphql/**
Dockerfile*
lib/graphql/**
lib/redirects/**
lib/rest/**
lib/webhooks/**
lib/search/indexes/**
package*.json
scripts/**
translations/**
content/actions/deployment/security-hardening-your-deployments/**

You'll need to revert all of the files you changed in that list using GitHub Desktop or git checkout origin/main <file name>. Once you get those files reverted, we can continue with the review process.

[cmwilson21]

@jnidzwetzki Thanks so much for opening a PR and linking it to your issue! ✨

I'll get this triaged for review ⚡

[sophietheking]

Hi @jnidzwetzki 👋 thanks for spotting this and fixing it, we really appreciate it. ✨ I'll get this merged for you! 🚀

[github-actions]

Thanks very much for contributing! Your pull request has been merged 🎉 You should see your changes appear on the site in approximately 24 hours. If you're looking for your next contribution, check out our help wanted issues ⚡