fix: upgrade ra-data-json-server from 3.4.1 to 3.5.3

Snyk has created this PR to upgrade ra-data-json-server from 3.4.1 to 3.5.3.

See this package in NPM:
https://www.npmjs.com/package/ra-data-json-server

See this project in Snyk:
https://app.snyk.io/org/gerdesque/project/acd9730a-8dd5-4c49-8d23-b4831e53dcac?utm_source=github&utm_medium=upgrade-pr

package.json

@@ -37,7 +37,7 @@
     "document-register-element": "1.14.3",
     "json-server": "^0.16.1",
     "prop-types": "^15.7.2",
-    "ra-data-json-server": "^3.4.1",
+    "ra-data-json-server": "^3.5.3",
     "ra-language-german": "^2.1.2",
     "react": "16.13.1",
     "react-admin": "^3.4.2",