fix(i18n): proofreading of the french translations (#2485)
fix(i18n): proofreading of the french translations (#2485)

fixed basic typos
replaced "s'assure que" by "vérifier que"
removed subjunctive forms
typography: homogenized apostrophes
typography: added spaces before : and !
fixed singular / plural
fixed genders
added some elisions of vowels

Closes issue #2484
dequelabs/axe-core,dequelabs/axe-core,dequelabs/axe-core,dequelabs/axe-core