Bump jimp from 0.6.4 to 0.9.3

Bumps [jimp](https://github.com/oliver-moran/jimp) from 0.6.4 to 0.9.3.
- [Release notes](https://github.com/oliver-moran/jimp/releases)
- [Changelog](https://github.com/oliver-moran/jimp/blob/master/CHANGELOG.md)
- [Commits](https://github.com/oliver-moran/jimp/compare/v0.6.4...v0.9.3)

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

package.json

@@ -51,7 +51,7 @@
     "form-data": "^2.3.3",
     "http-errors": "^1.7.1",
     "image-size": "^0.7.1",
-    "jimp": "^0.6.1",
+    "jimp": "^0.9.3",
     "jquery": "^3.3.1",
     "kcors": "^2.2.2",
     "koa": "^2.7.0",