Globally Toggle "Upload Replays of Lives" By Default

[MattyBoombalatty]

Describe the problem to be solved

When creating a new live, the option to automatically publish a replay when the live is finished is always checked. For instances, like ours, that have storage quotas, I think having this unchecked by default would be the best option, that way livestreams aren't arbitrarily cut off and we don't have to remind people who are unfamiliar with PeerTube how to turn off the functionality.

I know that we can turn off the function by default, but there are some people who are allowed to use the function. I know this is kind of an edge case, but I figured I'd make a feature request for anyone else who might have this same problem.

Describe the solution you would like

Allow administrators to set the default option for "automatically upload a replay when the live ends" for all new lives.