build: add bin/ to gitignore
build: add bin/ to gitignore

higebu/ignition,crawford/ignition,jonboulle/ignition,dgonyeo/ignition,marineam/ignition,higebu/ignition,coreos/ignition,ajeddeloh/ignition,AlexNPavel/ignition,higebu/ignition,coreos/ignition,crawford/ignition,jonboulle/ignition,marineam/ignition,trnubo/ignition,jonboulle/ignition,mischief/ignition,mischief/ignition,dgonyeo/ignition,AlexNPavel/ignition,AlexNPavel/ignition,coreos/ignition,trnubo/ignition,mischief/ignition,ajeddeloh/ignition,marineam/ignition,dgonyeo/ignition,trnubo/ignition,ajeddeloh/ignition