envelope parameters don't always update until next trigger

[ianhattwick]

This is an order of operations issue, where occasionally envelopes won't be updated with current CV values until their next trigger

Seen when using 'cartesian', in which

• a clock triggers the decay and also triggers a new step in cartesian
• the trigger hits the decay first, and triggers the envelope
• the trigger hits cartesian second, which updates the sequencer and sends a new decay time CV
• but the CV doesn't take effect until the next time the envelope is triggered