Setting avatar executable to gio open crashes Profanity

[jubalh]

It works with url open but doesnt for avatar.

Expected Behavior

/executable avatar "gio open" should set gio open as default opener for /avatar open.

Current Behavior

Crash

Possible Solution

Check GSubprocess instead of spawn.

Steps to Reproduce (for bugs)

1. /executable urlopen set "gio open %u"

2. `/url open ..select one

3. it works

4. /executable avatar "gio open""`

5. /avatar open somejid

6. crash

Environment

https://github.com/profanity-im/profanity/commit/9d094f73e39b18367fab814be26efabe3c468d28