Fix check-requirements: The assumptions with remote branch are not valid
anymore with Zuul v3, the change is on the proposed branch, check against
HEAD^1 instead.
Use the command module instead of script to get stdout in the
job-output.txt.gz file. Zuul v3 currently will not record the output from script
module in that file, only when command is used.
Note that the script module copied the file to the remote system - the
system where the tests are run - while command does not do this. But
the command is already on the remote system, use correct path for it.
Co-Authored-By: James E. Blair <corvus@inaugust.com>
Change-Id: Ib44332b4daf63b9d3fca6eadf0b4825614ca4aeb
58cac05a76