Hide horizontal scrollbar on admin tables when unnecessary

Author: futurGH

frontend/src/templates/AdminInvitesPage.mlx

@@ -141,7 +141,7 @@ let[@react.component] make
           </div>
       | None ->
           null )
-      <div className="overflow-x-auto">
+      <div className=(if List.length invites > 0 then "overflow-x-auto" else "overflow-x-hidden")>
         <table
           className="w-full grid border-collapse text-sm"
           style=(ReactDOM.Style.make

frontend/src/templates/AdminUsersPage.mlx

@@ -183,7 +183,7 @@ let[@react.component] make
           </div>
       | None ->
           null )
-      <div className="overflow-x-auto">
+      <div className=(if List.length actors > 0 then "overflow-x-auto" else "overflow-x-hidden")>
         <table
           className="w-full min-w-xl grid border-collapse text-sm"
           style=(ReactDOM.Style.make