catapult: fix broken run-tests catapult tracing

Authored by spectral.

Description

catapult: fix broken run-tests catapult tracing

Commit 97f52862b1bd thought this block was misindented, but it was not; the
indentation after that commit means we never log a catapult trace for individual
commands. Also, we've never emitted the "end" trace line when the test was
finished, so the trace viewer claims that these "did not finish", fixing that as
well.

Differential Revision: https://phab.mercurial-scm.org/D5214