add conference options to the broadcasts; implement auth to microsoft

spec/factories/broadcasts.rb

@@ -2,11 +2,16 @@ FactoryBot.define do
   factory :broadcast do
     association :project
     name "My Live Stream"
+    conference_option "zoom"
 
     transient do
       skip_create_callback false
     end
 
+    trait :ms_teams_conference do
+      conference_option "ms_teams"
+    end
+
     trait :with_stream do
       stream_uid "mux_stream"
       stream_key "mux_key"