Use preinstalled virtualenv on Jenkins nodes.

[tvalentyn]

[INFRA-16508]

DESCRIPTION HERE

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[tvalentyn]

R: @jasonkuster
cc: @udim
cc: @alanmyrvold

[tvalentyn]

Run Python Dataflow ValidatesRunner

[jasonkuster]

Changes LGTM. Is failure a KI?

[udim]

Another solution is to do the same as in #5146 (by @pabloem)

[pabloem]

In fact, these two scripts can now be made into one, with passing in attr set to IT or ValidatesRunner.

On Wed, May 9, 2018, 6:49 PM Udi Meiri (Ehud) ***@***.***> wrote: Another solution is to do the same as in #5146 <#5146> (by @pabloem <https://github.com/pabloem>) — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#5324 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/ABPc7KIK5KCxIIFHFVJmQ_kS5G1X-TAYks5tw5yXgaJpZM4T5EFt> .

-- Got feedback? go/pabloem-feedback

[tvalentyn]

Failure is a different issue, that's also needs fixing. I think we can merge this and work in parallel on migrating the suite to Gradle.

[jasonkuster]

Sounds good.