prod - add photo for sam

[paulstey]

This PR just adds a headshot for Sam to our About page.

Check the types of changes present in this PR:

• [ ] :bug: Bug
• [ ] :dragon: Feature
• [x] :frog: Data (data folder - people/opportunities)
• [ ] :dog: Content (content folder)
• [ ] :blowfish: Other. Specify:

Checklist:

• [x] Commitizen was used for all commits.
• [x] Local site looks as expected after changes.
• [x] Contributing guidelines were followed.
• [x] If changes affect development, was the README updated?

If PR to production

• [x] Development site (https://datasci.brown.edu) was checked and looks as expected.

[github-actions[bot]]

Admin Release Checklist

Before merging a pull request into production, which triggers a release to the production website, make sure the following is in order:

• [x] Staging looks as expected for all changes included in this PR
• [x] Triple check spelling
• [x] Triple check links work
• [x] Waiting period must be complete (see labels)