Change LAVA log filtering regexp to be more inclusive
Change LAVA log filtering regexp to be more inclusive

Previous expression captured only <LAVA_SIGNAL* messages what made some
of the unwanted LAVA log messages to slip under the radar. Changing
regexp to filter out everything that starts with <LAVA_* works better
for our purposes.

kernelci/kernelci-backend,kernelci/kernelci-backend