Comment 7 for bug 1782110

Em dashes cannot be part of a snap name.
They _could_ be part of an intentional 'snap set' command, something like
   snap set mysnap foo=—o—
in which case, if the "snap set" fails, the user will get the above message, followed by whatever error. Like so:

$ snap set bofh foo=—o—
Your command included some characters that look like dashes but are not:
    "snap set bofh foo=\u2014o\u2014"
in some situations you might find that when copying from an online source such
as a blog you need to replace “typographic” dashes and quotes with their ASCII
equivalent. Dashes in particular are homoglyphs on most terminals and in most
fixed-width fonts, so it can be hard to tell.

error: cannot perform the following tasks:
- Run configure hook of "bofh" snap (snap "bofh" has no "configure" hook)

I think this is reasonable unless we want to actually parse the em dashes, which seems like a lot more work for this corner case.