chore(web): drop eslint-plugin-flowtype

Which comes from the cockpit-starter-kit (see
agama-project#127) but it is actually not
needed since Agama does not use flowtype's annotation.

What is more, it isn't a cockpit-starter-kit dependency anymoer, see
cockpit-project/starter-kit@ab04f35

Author: dgdavid

web/package-lock.json

@@ -56,7 +56,6 @@
     "eslint": "^8.53.0",
     "eslint-config-prettier": "^9.1.0",
     "eslint-plugin-agama-i18n": "^0.1.0",
-    "eslint-plugin-flowtype": "^8.0.3",
     "eslint-plugin-i18next": "^6.0.3",
     "eslint-plugin-import": "^2.29.0",
     "eslint-plugin-n": "^16.3.1",