[Tails-l10n] [review] small icon fix in documentation

Ey there:

In this docs we are showing the wrong icon in a place (step 5) but
luckily the right icon is already on our lib/ folder:

https://tails.boum.org/doc/first_steps/reset/linux/

Please review emmapeel:docs/fix-linux-reset-screenshot

I did a commit for the markdown and another for the .po files... (i am
not sure if i committed correctly the fuzzy strings)

maybe a translator can have a look before asking for the merge?


https://git-tails.immerda.ch/emmapeel/tails/