main: setup GJS profiler when GJS_TRACE_FD is set

This is the same environment variable that will be used in GJS to auto-
connect Sysprof to the GJS profiler when the gjs binary is used.

!573
4 jobs for !573 with wip/chergert/gjs-trace-fd in 1 minute and 35 seconds (queued for 1 second)
detached
Status Job ID Name Coverage
  Review
passed #329091
check_commit_log

00:00:23

 
  Build
failed #329092
build

00:01:12

 
  Test
skipped #329093
test
skipped #329094
test-pot
 
Name Stage Failure
failed
build Build
Dependency gjs-1.0 found: NO found '1.57.2' but need: '>= 1.57.3'
Did not find CMake 'cmake'
Found CMake: NO
Dependency gjs-1.0 found: NO

meson.build:84:0: ERROR: Invalid version of dependency, need 'gjs-1.0' ['>= 1.57.3'] found '1.57.2'.

A full log can be found at /builds/GNOME/gnome-shell/build/meson-logs/meson-log.txt
ERROR: Job failed: exit code 1