[ENG-10383] fix: Navigating to the old /discover URL format should redirect to the current registry page (#925)

- Ticket: https://openscience.atlassian.net/browse/ENG-10383
- Feature flag: n/a

## Purpose
Navigating to the old /discover URL format should redirect to the current registry page.

https://osf.io/registries/dataarchive/discover and https://osf.io/registries/dataarchive/  


## Summary of Changes
add to registrations router mapping for providerId/discover

Author: mkovalua

src/app/features/registries/registries.routes.ts

@@ -49,6 +49,11 @@ export const registriesRoutes: Routes = [
       },
       {
         path: ':providerId',
+        redirectTo: ':providerId/discover',
+        pathMatch: 'full',
+      },
+      {
+        path: ':providerId/discover',
         loadComponent: () =>
           import('@osf/features/registries/pages/registries-provider-search/registries-provider-search.component').then(
             (c) => c.RegistriesProviderSearchComponent