components/PendingOwnerInviteRow: Use inviter.login instead of invited_by_username field

`invited_by_username` isn't actually sent anymore by the v2 (aka. `private`) API and it had been showing an empty column for 14 months now... 😅

Author: Turbo87

app/components/pending-owner-invite-row.hbs

@@ -19,8 +19,8 @@
     </div>
     <div>
       Invited by:
-      <LinkTo @route="user" @model={{@invite.invited_by_username}} data-test-inviter-link>
-        {{@invite.invited_by_username}}
+      <LinkTo @route="user" @model={{@invite.inviter.login}} data-test-inviter-link>
+        {{@invite.inviter.login}}
       </LinkTo>
     </div>
     <div local-class="date-column" data-test-date>