Rename image to better match terminology

wiki/src/doc/first_steps/start_tails.fa.po

wiki/src/doc/first_steps/start_tails.fr.po

wiki/src/doc/first_steps/start_tails.it.po

wiki/src/install/inc/screenshots/boot_loader_menu.png

wiki/src/install/inc/steps/mac_startup_disks.inline.html

wiki/src/install/inc/steps/restart_first_time.inline.de.po

wiki/src/install/inc/steps/restart_first_time.inline.es.po

wiki/src/install/inc/steps/restart_first_time.inline.fa.po

wiki/src/install/inc/steps/restart_first_time.inline.fr.po

wiki/src/install/inc/steps/restart_first_time.inline.it.po

wiki/src/install/inc/steps/restart_first_time.inline.pt.po

wiki/src/install/inc/steps/restart_second_time.inline.de.po

wiki/src/install/inc/steps/restart_second_time.inline.es.po

wiki/src/install/inc/steps/restart_second_time.inline.fa.po

wiki/src/install/inc/steps/restart_second_time.inline.fr.po

wiki/src/install/inc/steps/restart_second_time.inline.it.po

wiki/src/install/inc/steps/restart_second_time.inline.mdwn

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