Fix hosting signup link

Fixes https://github.com/vector-im/riot-web/issues/14500

element.io/app/config.json

@@ -10,7 +10,7 @@
         "https://scalar-staging.vector.im/api",
         "https://scalar-staging.riot.im/scalar/api"
     ],
-    "hosting_signup_link": "https://modular.im/services/matrix-hosting-riot?utm_source=riot-web&utm_medium=web",
+    "hosting_signup_link": "https://element.io/matrix-services?utm_source=riot-web&utm_medium=web",
     "bug_report_endpoint_url": "https://riot.im/bugreports/submit",
     "features": {
     },

element.io/develop/config.json

@@ -10,7 +10,7 @@
         "https://scalar-staging.vector.im/api",
         "https://scalar-staging.riot.im/scalar/api"
     ],
-    "hosting_signup_link": "https://modular.im/services/matrix-hosting-riot?utm_source=riot-web&utm_medium=web",
+    "hosting_signup_link": "https://element.io/matrix-services?utm_source=riot-web&utm_medium=web",
     "bug_report_endpoint_url": "https://riot.im/bugreports/submit",
     "features": {
         "feature_new_spinner": "labs",