cogl tests: Show the actual output from tests if VERBOSE is set

Writing tests' output to a log file makes them difficult to debug when
the test might be running on an autobuilder or CI system where only
stdout/stderr are recorded. This is particularly troublesome if a
failure is only reproducible on a particular autobuilder.

Recent Automake versions have the convention that detailed output from
failing tests is written to stdout/stderr, not just to log files, when
the VERBOSE environment variable is set; borrow that convention as a
trigger for producing detailed test output.

This was originally cogl!14, but applies equally to mutter's fork of cogl.

!1273

Signed-off-by: Simon McVittie <smcv@debian.org>
6 jobs for !1273 with wip/smcv/cogl-show-test-output in 8 minutes and 28 seconds (queued for 2 seconds)
detached
Status Job ID Name Coverage
  Review
passed #916238
check-commit-log

00:00:14

 
  Build
passed #916239
build-mutter

00:02:52

passed #916241
build-without-native-backend-and-wayland

00:01:47

passed #916240
build-without-opengl-and-glx

00:08:28

 
  Test
passed #916243
can-build-gnome-shell

00:01:42

passed #916242
test-mutter

00:04:56