CircleCI: Increase no-output timeout to 15 minutes for vendoring
CircleCI: Increase no-output timeout to 15 minutes for vendoring

Vendoring can take some time, depending on network-speed, so
reduce flakiness by increasing the default timeout, to prevent:

    make[1]: Entering directory '/go/src/github.com/docker/cli'
    rm -rf vendor
    bash -c 'vndr |& grep -v -i clone'
    2019/03/18 11:38:26 Collecting initial packages
    Too long with no output (exceeded 10m0s)

Signed-off-by: Sebastiaan van Stijn <64b2b6d12bfe4baae7dad3d018f8cbf6b0e7a044@gone.nl>

cpuguy83/cli,thaJeztah/cli,thaJeztah/cli,docker/cli,cpuguy83/cli,docker/cli