Apiserver: Refactor authenticator and authorizers (#101449)

* Clean up authenticator

* Cleanup authorizers and replace org_id and stack_id with namespace authorizer

* Remove dependency on org service

* Extract orgID from /apis/ urls and validate stack id

pkg/tests/apis/iam/iam_test.go

@@ -110,6 +110,10 @@ func TestIntegrationIdentity(t *testing.T) {
 		// Get just the specs (avoids values that change with each deployment)
 		found = teamClient.SpecJSON(rsp)
 		require.JSONEq(t, `[
+			{
+				"email": "admin-1",
+				"login": "admin-1"
+			},
 			{
 				"email": "admin-3",
 				"login": "admin-3"