travis: Run goveralls test target on shard 0.
travis: Run goveralls test target on shard 0.

Before commit 6f10800, the target was always run although its config is set to "Manual: false". In said commit I fixed test.go to respect the "Manual" field for the -shard execution mode as well.

Therefore, Travis needs to explicitly run this test now.

(In general: It's set to manual because it only makes sense to run it on Travis and not e.g. when running the tests locally in a Docker image.)

mattharden/vitess,enisoc/vitess,alainjobart/vitess,HubSpot/vitess,enisoc/vitess,vitessio/vitess,mahak/vitess,tirsen/vitess,rnavarro/vitess,rnavarro/vitess,sougou/vitess,rnavarro/vitess,pivanof/vitess,tirsen/vitess,alainjobart/vitess,applift/vitess,applift/vitess,mattharden/vitess,tinyspeck/vitess,mahak/vitess,applift/vitess,alainjobart/vitess,mattharden/vitess,tinyspeck/vitess,alainjobart/vitess,applift/vitess,vitessio/vitess,dcadevil/vitess,sougou/vitess,pivanof/vitess,HubSpot/vitess,tinyspeck/vitess,pivanof/vitess,pivanof/vitess,mattharden/vitess,mattharden/vitess,rnavarro/vitess,HubSpot/vitess,enisoc/vitess,sougou/vitess,sougou/vitess,rnavarro/vitess,mahak/vitess,mahak/vitess,rnavarro/vitess,dcadevil/vitess,davygeek/vitess,enisoc/vitess,davygeek/vitess,tirsen/vitess,pivanof/vitess,mattharden/vitess,davygeek/vitess,tinyspeck/vitess,mattharden/vitess,davygeek/vitess,rnavarro/vitess,tinyspeck/vitess,dcadevil/vitess,davygeek/vitess,mattharden/vitess,dcadevil/vitess,tirsen/vitess,enisoc/vitess,alainjobart/vitess,HubSpot/vitess,applift/vitess,tirsen/vitess,applift/vitess,tirsen/vitess,tirsen/vitess,applift/vitess,pivanof/vitess,rnavarro/vitess,mattharden/vitess,dcadevil/vitess,pivanof/vitess,pivanof/vitess,applift/vitess,dcadevil/vitess,sougou/vitess,vitessio/vitess,tirsen/vitess,mahak/vitess,vitessio/vitess,vitessio/vitess,alainjobart/vitess,HubSpot/vitess,mattharden/vitess,alainjobart/vitess,enisoc/vitess,enisoc/vitess,mahak/vitess,davygeek/vitess,davygeek/vitess,rnavarro/vitess,tinyspeck/vitess,alainjobart/vitess,mahak/vitess,dcadevil/vitess,sougou/vitess,applift/vitess,vitessio/vitess,mahak/vitess,HubSpot/vitess,vitessio/vitess,vitessio/vitess,pivanof/vitess,sougou/vitess,tirsen/vitess,HubSpot/vitess,applift/vitess,tinyspeck/vitess,HubSpot/vitess,sougou/vitess