ttcn3-testsuites.yml: Add job for ttcn3-sccp-test

Only for nightly, not latest, since example/sccp_demo_user is not
installed by autotools and debian packages, so only in nightly where we
build from source we are able to copy it to docker image manually.

Related: OS#4343
Change-Id: Ia0a68d74215bdc1bc6319241d60f858312fa14e9
1 file changed