[Python] flake8 warnings are not failing CI builds

[asfimport]

I think this is because the flake8 calls are inside a bash function. We'll need to do a bit of work on our CI scripts to make sure the set -e results in flake8 call propagating the error code

Reporter: Wes McKinney / @wesm
Assignee: Wes McKinney / @wesm

_{Note: This issue was originally created as ARROW-1430. Please see the migration documentation for further details.}

[asfimport]

Wes McKinney / @wesm:
PR: #1059

[asfimport]

Wes McKinney / @wesm:
Issue resolved by pull request 1059
#1059