add sketchfab icon (adityatelange#998)

Author: pinfel

data/svg.toml

@@ -604,6 +604,11 @@ shutterstock = '''
         stroke-linecap="square" stroke-linejoin="miter" />
 </svg>
 '''
+sketchfab = '''
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 2000 2000" fill="currentColor">
+    <path d="m1000 0c-552.32 0-1000 447.72-1000 1000s447.68 1000 1000 1000 1000-447.72 1000-1000-447.6-1000-1000-1000zm-86.88 1595.07-431.12-248.86v-502l431.12 232.79zm76.8-636.19-510.08-270.38 510.08-294.5 510.16 294.5zm510.48 388.29-429.52 248v-516.17l429.52-232z"/>
+</svg>
+'''
 slack = '''
 <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2"
     stroke-linecap="round" stroke-linejoin="round">