check for virtualservices before running clean up

[ukclivecox]

Fixes #1631

[seldondev]

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[seldondev]

Sun Mar 29 16:36:15 UTC 2020
The logs for [lint] [2] will show after the pipeline context has finished.
https://github.com/SeldonIO/seldon-core/blob/gh-pages/jenkins-x/logs/SeldonIO/seldon-core/PR-1632/2.log

impatient try
jx get build logs SeldonIO/seldon-core/PR-1632 --build=2

[seldondev]

Sun Mar 29 16:36:16 UTC 2020
The logs for [pr-build] [1] will show after the pipeline context has finished.
https://github.com/SeldonIO/seldon-core/blob/gh-pages/jenkins-x/logs/SeldonIO/seldon-core/PR-1632/1.log

impatient try
jx get build logs SeldonIO/seldon-core/PR-1632 --build=1