chore(deps): bump unpic from 3.18.0 to 4.1.2

Bumps [unpic](https://github.com/ascorbic/unpic) from 3.18.0 to 4.1.2.
- [Release notes](https://github.com/ascorbic/unpic/releases)
- [Changelog](https://github.com/ascorbic/unpic/blob/main/CHANGELOG-old.md)
- [Commits](ascorbic/unpic@v3.18.0...v4.1.2)

---
updated-dependencies:
- dependency-name: unpic
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

package-lock.json

@@ -26,7 +26,7 @@
     "rehype-slug": "^6.0.0",
     "rehype-toc": "^3.0.2",
     "typescript-esbuild": "^0.4.10",
-    "unpic": "^3.18.0"
+    "unpic": "^4.1.2"
   },
   "devDependencies": {
     "@astrojs/mdx": "^2.3.1",