support to get/set segment_leaderboard_opt_out on activities

[arkarkark]

It doesn't look like the api supports getting/setting the new segment_leaderboard_opt_out attribute on activities. Do you know if/when support for that will be added?

I found the name by looking at what the front end does, when it PUTs to https://www.strava.com/athlete/training_activities/xxxxxxxx

Thanks so much