bug#22709: wxmaxima missing lots of toolbar icons

[Royce Strange]

Hello.

Looks like commit de477809d77393b8fb00d99cd35d65f77d157726
by Sou Bunnbu should have fixed this.

Validating using a current guix that icons load in wxmaxima
without having to load in anything else:

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guix --version
guix (GNU Guix) e7a7a483bcda6ec60d9dff3b3aba88dababe035c

$ guix environment --pure --ad-hoc wxmaxima -- wxmaxima
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Chris Marusich's suggestion to install an icon theme package into 
your profile will help with most other general icon issues.

Going to go ahead and close.
(note: there is bug#39955 to address the broken help menu)