feat: add Hadley Garrett to /about page (#335)

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## PR Checklist

- [x] Addresses an existing open issue: fixes N/A
- [x] That issue was marked as [`status: accepting
prs`](https://github.com/JoshuaKGoldberg/boston-ts-website/issues?q=is%3Aopen+is%3Aissue+label%3A%22status%3A+accepting+prs%22)
- [x] Steps in
[CONTRIBUTING.md](https://github.com/JoshuaKGoldberg/boston-ts-website/blob/main/.github/CONTRIBUTING.md)
were taken

## Overview

<!-- Description of what is changed and how the code change does that.
-->

✨

app/routes/about.tsx

@@ -61,6 +61,9 @@ export default function About() {
 				<li>
 					<strong>Sean Sanker Jr</strong>
 				</li>
+				<li>
+					<strong>Hadley Garrett</strong>
+				</li>
 			</ul>
 			<Heading level={3}>The Website</Heading>
 			<BodyText>

cspell.json

@@ -16,6 +16,7 @@
 		"bostonts",
 		"clsx",
 		"currentcolor",
+		"Hadley",
 		"isbot",
 		"Jérémie",
 		"knip",