Serialize the command line to metadata.txt. The expected format in the
metadata.txt is like below:

	cmdline.argc : 6
	cmdline.argv[0] : ./build/runner/igt_runner
	cmdline.argv[1] : -o
	cmdline.argv[2] : --test-list
	cmdline.argv[3] : /tmp/testlist.txt
	cmdline.argv[4] : build/tests/
	cmdline.argv[5] : /tmp/results

Reviewed-by: Gustavo Sousa <gustavo.sousa@intel.com>
Tested-by: Peter Senna Tschudin <peter.senna@linux.intel.com>
Reviewed-by: Peter Senna Tschudin <peter.senna@linux.intel.com>
Link: https://lore.kernel.org/r/20250207231039.2883195-11-lucas.demarchi@intel.com


Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>