Revert "Temporary allow to fail Trunk rally tests"

This reverts commit 733e1d6726.

That is no longer needed with the merge of
https://review.opendev.org/#/c/686571/

Change-Id: I85f3d51dd7066b8be6adfc183f120d3d3b4f1e77
Closes-Bug: #1845479

rally-jobs/ovn.yaml

@@ -304,10 +304,6 @@
           neutron:
             network: -1
             port: 1000
-      sla:
-        # TODO(mjozefcz): Remove this when bug #1845479 will be fixed.
-        failure_rate:
-          max: 100
     -
       title: Floating IP related workloads
       workloads: