Flake8 package checking python coding style: test_mkldnn.py, small tidy up

[mozga-intel]

Description

This pull request tidies up the python unit-test file.

Confuguration

Flake8 package is required to get a result like please have a look: that: https://flake8.pycqa.org/en/latest/#. The main dir contains .flake8 file with a configuration, as follows: [Example]

[flake8]
select = B,C,E,F,P,T4,W,B9
max-line-length = 120
ignore =
    E203,E305,E402,E501,E721,E741,F405,F821,F841,F999,W503,W504,C408,E302,W291,E303,F403
    EXE001,
    B007,B008, E722
    C400,C401,C402,C403,C404,C405,C407,C411,C413,C414,C415
optional-ascii-coding = True
exclude = 
    ./.git,
    ./.build,
    *.pyi

Future consideration

This process should be added to a hook and it could be run before any commit (run lint). Additionally, CI should have a mechanism to detect differences between versions.

Checklist

Essentials

• PR's title starts with a category (e.g. [BUGFIX], [MODEL], [TUTORIAL], [FEATURE], [DOC], etc)
• Changes are complete (i.e. I finished coding on this PR)
• All changes have test coverage
• Code is well-documented

Changes

• Feature1, tests, (and when applicable, API doc)
• Feature2, tests, (and when applicable, API doc)

Comments

• If this change is a backward incompatible change, why must this change be made.
• Interesting edge cases to note here

[mxnet-bot]

Hey @mozga-intel , Thanks for submitting the PR
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[sfraczek]

LGTM

[mozga-intel]

@mxnet-bot run ci [unix-gpu]

[mxnet-bot]

Jenkins CI successfully triggered : [unix-gpu]

[mozga-intel]

@mxnet-bot run ci [unix-gpu]

[mxnet-bot]

Jenkins CI successfully triggered : [unix-gpu]

[mozga-intel]

@mxnet-bot run ci [unix-gpu]

[mxnet-bot]

Jenkins CI successfully triggered : [unix-gpu]