Bump sharp from 0.30.7 to 0.31.2 in /api

Bumps [sharp](https://github.com/lovell/sharp) from 0.30.7 to 0.31.2.
- [Release notes](https://github.com/lovell/sharp/releases)
- [Changelog](https://github.com/lovell/sharp/blob/main/docs/changelog.md)
- [Commits](lovell/sharp@v0.30.7...v0.31.2)

---
updated-dependencies:
- dependency-name: sharp
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Author: dependabot[bot]

api/package-lock.json

@@ -31,7 +31,7 @@
     "nodemailer": "^6.7.8",
     "reallydangerous": "^2.1.0",
     "sanitize-filename": "^1.6.3",
-    "sharp": "^0.30.7",
+    "sharp": "^0.31.2",
     "ws": "^8.11.0"
   }
 }