Maintenance: Disable M365 spec.

spec/integration/microsoft365_spec.rb

@@ -6,6 +6,11 @@ RSpec.describe 'Microsoft365 XOAUTH2', integration: true, required_envs: %w[MICR
     create(:microsoft365_channel).tap(&:refresh_xoauth2!)
   end
 
+  # TODO: Remove this once we have a better way for testing M365.
+  before do
+    skip 'This test example requires a valid account for M365.'
+  end
+
   context 'when probing inbound' do
     before do
       options = channel.options[:inbound][:options]