Improves validation in getRolesByName endpoint (#25215)

* Improves validation in getRolesByName endpoint

* Updates the max constant and fixes linter

* Adds a mechanism to split roles in chunks in the webapp client

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Co-authored-by: Mattermost Build <build@mattermost.com>

server/i18n/en.json

@@ -2682,6 +2682,10 @@
     "id": "api.restricted_system_admin",
     "translation": "This action is forbidden to a restricted system admin."
   },
+  {
+    "id": "api.roles.get_multiple_by_name_too_many.request_error",
+    "translation": "Unable to get that many roles by name. Only {{.MaxNames}} roles can be requested at once."
+  },
   {
     "id": "api.roles.patch_roles.license.error",
     "translation": "Your license does not support advanced permissions."