Linked account - paged listing of IdPs

Motivation:

On keycloak’s account management console, if a realm has a lot of identity providers, the user is presented with a huge list which he has to scroll in order to find the desired identity provider to link his account with, since there is no search/filtering in the UI. Moreover, a lot of information is fetched, making the webpage quite resource demanding in terms of memory and network bandwidth.

Design proposal:

We propose to perform minimal changes on the current design and add a paging and filtering on both {Linked Login Providers, Unlinked Login Providers} lists.
Our enhancement is done by making as few as possible changes on both the react and java sides.
So, with the following minimal changes: 

• on the backend side (java), we enabled LinkedAccountRepresentation items to be fetched in pages in LinkedAccountsResource.java
• on the frontend side (react/patternfly), we added a patternfly Pagination element to drive the requests of the pages from the backend and also added a filter, to filter out (server-side) the response

The loading times are hugely improved:

We have ~4300 IdPs in our keycloak and we measured the loading times and the idp-related data fetching.

We also attach two screenshots to showcase the UI changes:

Before:

After: