Audit action options are not indented

[matthew-white]

The audit action select element in /system/audits renders a series of options. Some options represent categories of actions, while others represent specific actions. The specific actions are supposed to be indented, but aren't right now:

I'm guessing this is related to a change in how Vue handles white space and this bug in particular. If we don't want to wait for that bug to be resolved, I think we could also fix it by moving the non-breaking spaces from the template to actionOptions (specifically having actionOption() prefix the text with the non-breaking spaces).