bus tests: Shut down audit socket

Some CI environments run build-time tests as root with CAP_AUDIT_WRITE.
In this case we need to close the audit socket so that it will not be
reported as leaked.

Signed-off-by: Simon McVittie <smcv@collabora.com>
12 jobs for pass-tests-if-root in 9 minutes and 13 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Build
manual #396658
allowed to fail manual
build:buster
passed #396652
build:cmake

00:04:52

passed #396649
build:debug

00:09:13

manual #396654
allowed to fail manual
build:i686-w64-mingw32-cmake
passed #396653
build:i686-w64-mingw32-debug

00:02:45

manual #396657
allowed to fail manual
build:jessie
manual #396651
allowed to fail manual
build:legacy
passed #396648
build:production

00:06:33

manual #396650
allowed to fail manual
build:reduced
passed #396655
build:x86_64-w64-mingw32

00:03:24

passed #396656
build:x86_64-w64-mingw32-cmake-debug

00:02:58

manual #396659
allowed to fail manual
build:xenial