Redirect and refetch on Invitation accepted user action

[bobbykolev]

https://github.com/alkem-io/client-web/issues/5813

On invitation Accept -> refetchPendingInvitations & try to navigate to the Space; On invitation Reject -> refetchPendingInvitations & open back the pending memberships Dialog;

The changes were applied to the Dashboard Widget's Pending Memberships and the User Menu's Pending Memberships.

There's one more place with similar logic -> Apply button on top of the Space. There's no need for redirection there.