Fix log line translation key error
Fix log line translation key error

Fix logic when translating log line numbers, in the case where the log
line number is not in the translation map.

Fixes: db7ab5dae624 ("Clean LAVA test logs")
Signed-off-by: Guillaume Tucker <e7e20b7c30f19d4ca6b81319ef81bf200369d137@collabora.com>

kernelci/kernelci-backend,kernelci/kernelci-backend