software/slapos-testing: add lmsensors in $PATH
slapos.core test suite needs sensors command in $PATH
https://lab.nexedi.com/nexedi/slapos.core/commit/7467ef4c18bff607312578b991c9b69c5572a7e8#note_71574
slapos.core test suite needs sensors command in $PATH
https://lab.nexedi.com/nexedi/slapos.core/commit/7467ef4c18bff607312578b991c9b69c5572a7e8#note_71574