[BEAM-9061] Add version guards to requirements file for integration tests.

[tvalentyn]

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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.

[tvalentyn]

r: @udim

[tvalentyn]

Run Python 2 PostCommit

[udim]

I don't like adding yet another location with version numbers. I wish we a single SoT for versioning.

[udim]

Opened https://issues.apache.org/jira/browse/BEAM-9127 for postcommit py2:crossLanguagePortableWordCount failure.
Have not tracked down root cause for py2:hdfsIntegrationTest yet.

[tvalentyn]

Thanks, @udim. Opened https://issues.apache.org/jira/browse/BEAM-9130 for HDFS failure.

[tvalentyn]

Also checked that we now use pyhamcrest==1.10.1 on DF workers.

I 2020-01-15T18:01:18.297051Z Executing: /usr/local/bin/pip install -r /var/opt/google/dataflow/requirements.txt --no-index --no-deps --find-links /var/opt/google/dataflow 
I 2020-01-15T18:01:18.465683Z   Building wheel for pyhamcrest (setup.py): finished with status 'done' 
I 2020-01-15T18:01:18.466534Z   Created wheel for pyhamcrest: filename=PyHamcrest-1.10.1-cp27-none-any.whl size=48899 sha256=7123cf4cce0b8b917bf7dd1f286a4c051bf090f70347b1495243edf888eaa03a 
I 2020-01-15T18:01:18.466742Z   Stored in directory: /root/.cache/pip/wheels/7c/ea/7d/664d2b28854ea324717ed693c92c042db5b478b67962637a38 

[aaltay]

Does pyhamcrest > 1.10.0 work with python 2?

[tvalentyn]

1.10.1 does, 2.0.0 does not.