GNOME Shell's captive portal helper should be optional, to ensure it's possible for customers to uninstall WebKitGTK. Let's move it to a subpackage. For RHEL 9 and RHEL 8, we can instead just make sure that no JS ERRORs are printed when failing to launch the portal helper. Currently that looks like:

Oct 18 13:26:10 rocky8 gnome-shell-por[4306]: JS ERROR: Error: Requiring WebKit2, version none: Typelib file for namespace 'WebKit2' (any version) not found
                                              @resource:///org/gnome/shell/portalHelper/main.js:3:7
                                              @<main>:1:7
Oct 18 13:26:10 rocky8 gnome-shell-por[4306]: Execution of main.js threw exception: Script <main> threw an exception

Customers will probably complain about this.