minor #394 [Maintenance][Travis] Use stable composer (lchrusciel)
minor #394 [Maintenance][Travis] Use stable composer (lchrusciel)

This PR was merged into the 1.7 branch.

Discussion
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Commits
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8b3ae3a492b1029d26fe19efffbf0dc84862f813 [Maintenance][Travis] Use stable composer

Sylius/Sylius-Standard,Sylius/Sylius-Standard,Sylius/Sylius-Standard