Unknown prop `fit` on <svg> tag

[valeriisukhov]

Hello!
Instant getting this error:

Warning: Unknown prop `fit` on <svg> tag. Remove this prop from the element. For details, see https://fb.me/react-unknown-prop
    in svg (created by CloseIcon)
    in CloseIcon (created by Step)
    in div (created by Step)
    in div (created by Step)
    in Step (created by WalkThru)
    in div (created by Wrapper)
    in Wrapper (created by WalkThru)
    in WalkThru

Simple remove of CloseIcon.js line 35 fit from svg file make things work.
Can you heal this thing?