Remove legacy scenario multinode job for nova

The legacy job 'legacy-tempest-dsvm-neutron-scenario-multinode-lvm-multibackend'
has been migrated to tempest repo as "tempest-sceanrio-all" [1].

"tempest-sceanrio-all" job runs
- all scenario tests including slow tests - same as old job
- it exclude the live migration api tests - these tests are covered
                                            by "nova-live-migration"

New job "tempest-sceanrio-all" will be added on nova gate
by- https://review.openstack.org/#/c/583840/

This commit removes the old job entry for nova from project.yaml and
dependent patch adds the corresponding new job in nova gate.

[1] http://git.openstack.org/cgit/openstack/tempest/tree/.zuul.yaml#n147

Depends-On: https://review.openstack.org/#/c/567697/

Change-Id: I9a7974dcac2663c6c14b629c47350ec52487e3f6

zuul.d/projects.yaml

@@ -9558,21 +9558,6 @@
               - ^tests-py3.txt$
               - ^tools/.*$
               - ^tox.ini$
-        - legacy-tempest-dsvm-neutron-scenario-multinode-lvm-multibackend:
-            irrelevant-files:
-              - ^(placement-)?api-.*$
-              - ^(test-|)requirements.txt$
-              - ^.*\.rst$
-              - ^.git.*$
-              - ^doc/.*$
-              - ^nova/hacking/.*$
-              - ^nova/locale/.*$
-              - ^nova/tests/.*$
-              - ^releasenotes/.*$
-              - ^setup.cfg$
-              - ^tests-py3.txt$
-              - ^tools/.*$
-              - ^tox.ini$
         - legacy-tempest-dsvm-neutron-src-oslo.versionedobjects:
             irrelevant-files:
               - ^(placement-)?api-.*$