Fixes grammar and phrasing on envvar how-to
Fixes grammar and phrasing on envvar how-to

fkazimierczak/flask,drewja/flask,fkazimierczak/flask,pallets/flask,drewja/flask,pallets/flask,drewja/flask,mitsuhiko/flask,mitsuhiko/flask,pallets/flask,tristanfisher/flask,fkazimierczak/flask,tristanfisher/flask