Ensure SSL CA certificates are installed for curl

On openSUSE, ensure that the ca-certificates-mozilla package is
installed to avoid curl aborting with

  curl: (60) SSL certificate problem: unable to get local issuer certificate

when trying to download the pip source tarball.

Change-Id: Iaf74204ea5330e9abf56f6c9d5a0f9d83992aa59
Merge "Ensure SSL CA certificates are installed for curl"