Changes

jobs/ttcn3-testsuites{,-testenv}: add duration comments

Add the current "last duration" time from the jenkins jobs as comment,
so we have a rough idea of how long these jobs take and can distribute
them more evenly throughout the days. Even though the durations will
change over time, this gives a good indicator of whether a job runs a
few minutes or 1 or even 2 hours.

Change-Id: Iee1af60f3f76663eb7af562821a825640d53ee1e