fix: enable stripInternal to avoid exposing type augmentations (#765)

## PR Checklist

- [x] Addresses an existing open issue: fixes #759 
- [x] That issue was marked as [`status: accepting
prs`](https://github.com/JoshuaKGoldberg/ts-api-utils/issues?q=is%3Aopen+is%3Aissue+label%3A%22status%3A+accepting+prs%22)
- [x] Steps in
[CONTRIBUTING.md](https://github.com/JoshuaKGoldberg/ts-api-utils/blob/main/.github/CONTRIBUTING.md)
were taken

## Overview

Author: kirkwaiblinger

tsconfig.json

@@ -10,7 +10,8 @@
 		"skipLibCheck": true,
 		"sourceMap": true,
 		"strict": true,
-		"target": "ES2022"
+		"target": "ES2022",
+		"stripInternal": true
 	},
 	"include": ["src", "typings"]
 }