[BEAM-8229] Exclude python 3-specific test files from running in post-commit

[chadrik]

Fixes#9098 and removes the need for #9565.

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Post-Commit Tests Status (on master branch)

Lang	SDK	Apex	Dataflow	Flink	Gearpump	Samza	Spark
Go		---	---		---	---
Java
Python		---			---	---
XLang	---	---	---		---	---	---

Pre-Commit Tests Status (on master branch)

---	Java	Python	Go	Website
Non-portable
Portable	---		---	---

See .test-infra/jenkins/README for trigger phrase, status and link of all Jenkins jobs.

[chadrik]

R: @aaltay
R: @robertwb

Here's a quick fix if you want to use this instead of reverting and resubmitting #9098.

It would be good if we could preemptively run post-commit test, since running the integration tests on my laptop seems like a bit of a non-starter.

[chadrik]

Run Python PostCommit

[aaltay]

Run Python 2 PostCommit

[chadrik]

Run Python 3.5 PostCommit

[chadrik]

Run Python 3.6 PostCommit

[robertwb]

Thanks for figuring this out; let's see if it fixes all the tests.

[chadrik]

I'm happy to clean up my own mess. Sorry about the downtime, still learning my way around the build system.

[chadrik]

@robertwb speaking of builds, you may be interested to weigh in on this ticket: https://jira.apache.org/jira/projects/BEAM/issues/BEAM-8213

[chadrik]

Looks like this is ready to go

[markflyhigh]

Thank you @chadrik for this quick fix! I can merge since you got enough approvals.