Install mawk-1.3.4 on transition-logs-1

As well as needing this version of mawk for Jenkins jobs, we also
need it on transition-logs-1 for actually doing the processing of
the logfiles, which are uploaded onto there.
Merge pull request #109 from alphagov/mawk_1_3_4_on_transition_logs

Install mawk-1.3.4 on transition-logs-1