Airflow: Add missing `labels` parameter to MLEngineTrainingOperator

[xor-xor]

Description

MLEngineTrainingOperator doesn't expose labels parameter, which is kind of surprising, considering that operators for BigQuery provide it (see e.g. here).

BTW, this also applies to MLEngineBatchPredictionOperator.

Use case / motivation

Accounting, mostly - with a considerable number of training/prediction jobs launched daily on ML Engine / AI Platform, labels become crucial for this task.

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[mik-laj]

Hi. Would you like to prepare a PR to fix this problem? I will gladly support you if you have any questions.

[xor-xor]

Would you like to prepare a PR to fix this problem?

Hard to say... Seems to be an easy thing to implement, but I'm a bit short on time recently. We will see 🙂

[coopergillan]

I can give a shot at picking this up.

[mik-laj]

@coopergillan I assigned you to this ticket.

[coopergillan]

@xor-xor - here ya go. Hoping this is what you had in mind!

https://github.com/apache/airflow/pull/10222

cc: @mik-laj @turbaszek

[xor-xor]

@xor-xor - here ya go. Hoping this is what you had in mind!

Yep, exactly what I was looking for before I opened this issue. Thank you! 👍🏻 🙂