cogl/tests: Use less verbose run-tests.sh on single tests run by meson

Use less verbose output when run-tests.sh is running only a test and we're
requested for less verbose output.

Also write the test name first of running it.

GNOME/mutter!442
3 jobs for !442 with meson-test-suites in 11 minutes and 14 seconds (queued for 2 seconds)
detached
Status Job ID Name Coverage
  Review
passed #275224
check-commit-log

00:01:59

 
  Build
passed #275225
build-mutter

00:02:28

 
  Test
passed #275226
test-mutter

00:06:46