Command "require-dev" is not defined.

Composer changed the command from require-dev to require --dev: https://github.com/micheh/w3c-validator/issues/3

changed the description

assigned to @jurgenhaas

added Todo label

mentioned in commit 01d94bea

created merge request !1 (merged) to address this issue

mentioned in merge request !1 (merged)

@richardpapp I've left a review in the MR for you.

assigned to @richardpapp and unassigned @jurgenhaas

added Doing label and removed Todo label

mentioned in commit f9eaa779

closed with merge request !1 (merged)

removed Doing label