json2junit.py: write the test duration if provided in json
json2junit.py: write the test duration if provided in json

Recent Yocto versions added support for this, so if the duration
is present it is written into the junit (time is a valid paramer
with the same meaning).

Signed-off-by: Alexander Kanavin <bb799e51918c8b2e3484e7ea6ce921f01deb0efc@gmail.com>

Pelagicore/vagrant-cookbook,Pelagicore/vagrant-cookbook,Pelagicore/vagrant-cookbook