fix(portal): Throttle reqs/sec and scheduled frequency on Okta sync jobs (#6794)

Why:

* Our current Okta sync job has no throttle, which has caused an issue
with customers that have other applications hitting their Okta API by
going over their API rate limits. By throttling the requests per second
and by lowering the frequency of how often the job runs we should
hopefully aleviate any Okta API rate limiting issues. This will come at
the expense of syncs taking longer and not happening as often, however,
this tradeoff seems worthwhile to ensure Firezone isn't hindering a
customers use of their Okta API.

Closes: #6748

---------

Signed-off-by: Brian Manifold <bmanifold@users.noreply.github.com>
Co-authored-by: Jamil <jamilbk@users.noreply.github.com>

elixir/apps/domain/lib/domain/auth/adapters/okta/api_client.ex

@@ -105,6 +105,9 @@ defmodule Domain.Auth.Adapters.Okta.APIClient do
     headers = headers ++ [{"Authorization", "Bearer #{api_token}"}]
     request = Finch.build(:get, uri, headers)
 
+    # Crude request throttle, revisit for https://github.com/firezone/firezone/issues/6793
+    :timer.sleep(:timer.seconds(1))
+
     with {:ok, %Finch.Response{headers: headers, body: response, status: status}}
          when status in 200..299 <- Finch.request(request, @pool_name),
          {:ok, list} <- Jason.decode(response) do

elixir/apps/domain/lib/domain/auth/adapters/okta/jobs/sync_directory.ex

@@ -1,7 +1,7 @@
 defmodule Domain.Auth.Adapters.Okta.Jobs.SyncDirectory do
   use Domain.Jobs.Job,
     otp_app: :domain,
-    every: :timer.minutes(5),
+    every: :timer.minutes(20),
     executor: Domain.Jobs.Executors.Concurrent
 
   alias Domain.Auth.Adapter.OpenIDConnect.DirectorySync