build(deps): bump @types/leaflet from 1.9.19 to 1.9.21

Bumps [@types/leaflet](https://github.com/DefinitelyTyped/DefinitelyTyped/tree/HEAD/types/leaflet) from 1.9.19 to 1.9.21.
- [Release notes](https://github.com/DefinitelyTyped/DefinitelyTyped/releases)
- [Commits](https://github.com/DefinitelyTyped/DefinitelyTyped/commits/HEAD/types/leaflet)

---
updated-dependencies:
- dependency-name: "@types/leaflet"
  dependency-version: 1.9.21
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

package.json

@@ -58,7 +58,7 @@
     "@types/d3-cloud": "^1.2.9",
     "@types/d3-selection": "^3.0.11",
     "@types/geojson": "^7946.0.16",
-    "@types/leaflet": "^1.9.19",
+    "@types/leaflet": "^1.9.21",
     "@types/node-fetch": "^2.6.12",
     "bcryptjs": "^3.0.2",
     "canvas-confetti": "^1.9.3",