Remove HHVM testing from travis-ci configuration
Remove HHVM testing from travis-ci configuration

Laravel dropped support for HHVM since version 5.3. This package's
integration tests use Symfony features that do not support HHVM. For
these reasons, we have no need to test this branch on HHVM.

Signed-off-by: Cy Rossignol <31ace4ad1831aae866cd7951a842ca3e38f21981@rossignols.me>

monospice/laravel-redis-sentinel-drivers,monospice/laravel-redis-sentinel-drivers