Add workflow to validate the landscape.yml file

[tegioz]

Pre-submission checklist:

Please check each of these after submitting your pull request:

• Are you only including a repo_url if your project is 100% open source? If so, you need to pick the single best GitHub repository for your project, not a GitHub organization.
• Is your project closed source or, if it is open source, does your project have at least 300 GitHub stars?
• Have you picked the single best (existing) category for your project?
• Does it follow the other guidelines from the new entries section?
• Have you added your SVG to hosted_logos and referenced it there?
• Does your logo clearly state the name of the project/product and follow the other logo guidelines?
• Does your project/product name match the text on the logo?
• Have you verified that the Crunchbase data for your organization is correct (including headquarters and LinkedIn)?
• ~30 minutes after opening the pull request, the CNCF-Bot will post the URL for your staging server. Have you confirmed that it looks good to you and then added a comment to the PR saying "LGTM"?

[netlify]

✅ Deploy Preview for landscape ready!

Name	Link
🔨 Latest commit	cf1ff9c
🔍 Latest deploy log	https://app.netlify.com/sites/landscape/deploys/64e73cb04d2f3a0007fad36c
😎 Deploy Preview	https://deploy-preview-3473--landscape.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

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To edit notification comments on pull requests, go to your Netlify site configuration.

[netlify]

✅ Deploy Preview for landscape ready!

Name	Link
🔨 Latest commit	c1733ec
🔍 Latest deploy log	https://app.netlify.com/sites/landscape/deploys/64e73d4a72b1720008cee22b
😎 Deploy Preview	https://deploy-preview-3473--landscape.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify site configuration.