Remove old install-guide-jobs from murano
Remove old install-guide-jobs from murano

In newer brances (pike, queens, ..., master) install-guide-jobs does
not do anything:

As install-guide-jobs template [1] includes the
build-openstack-install-guide job [2], which runs only for branches
stable/newton and stable/ocata, but murano does not have install
guides in those branches, the install-guide-jobs can be safely removed.

[1] https://opendev.org/openstack/openstack-zuul-jobs/src/branch/master/zuul.d/project-templates.yaml#L1139-L1151
[2] https://opendev.org/openstack/openstack-zuul-jobs/src/branch/master/zuul.d/jobs.yaml#L687-L704

Change-Id: I6bfcd7ce762ea16d6b78f13fcb85754f46cc5763

openstack-infra/project-config,openstack-infra/project-config