added github-handle property for Robert Schacht

[saiteja-siddana]

Fixes #7292

What changes did you make?

• I modified _projects/design-systems.md by adding 'github-handle' key below the 'name: Robert Schacht' key/value pair.

Why did you make the changes (we will use this info to test)?

• This change is intended to reduce redundancy in the project file by replacing 'github' and 'picture' key/value pairs.

Screenshots of Proposed Changes To The Website (if any, please do not include screenshots of code changes)

• No visual changes to the website. The new key is not part of a display card.

[github-actions]

Want to review this pull request? Take a look at this documentation for a step by step guide!

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From your project repository, check out a new branch and test the changes.

git checkout -b saiteja-siddana-add-github-handle-7292 gh-pages
git pull https://github.com/saiteja-siddana/website.git add-github-handle-7292

[k-cardon]

Hi Saiteja, this looks good! Pull request written correctly, code corrects the issue, and I verified that your branch does not change the appearance of the website.

[k-cardon]

Looks correct!

[jphamtv]

Hi @saiteja-siddana,

• You created the pull request using the correct branch
• The issue is properly linked to the pull request
• Your summary of changes is clear and concise
• Your code change correctly uses spaces instead of tabs

Great work. Thanks for your contribution to resolving this issue!