Fix for the ThresholdCheckOperator problem

[DanilBaibak]

The fix for the issue #9309 regarding the problem with ThresholdCheckOperator.

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[boring-cyborg]

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[mik-laj]

@DanilBaibak We had problems with CI. Can you do rebase?

[eladkal]

Tested with Presto the suggested fix solves the issue.

[2020-06-17 20:40:59,820] {playground.py:197} INFO - Log from test-fix:
result: 4
task_id: threshold_check_new
min_threshold: 1.0
max_threshold: 6.0
within_threshold: True
[2020-06-17 20:40:59,820] {playground.py:188} INFO - Test threshold_check_new Successful.

[DanilBaibak]

Hi @mik-laj! Seems, tests passed and @eladkal tested the fix. Can we move forward with PR?

[mik-laj]

@DanilBaibak Can you do a rebase? This change is a bit old.

[boring-cyborg]

Awesome work, congrats on your first merged pull request!