[Bugfix][SDK] pod has no metadata attr anymore in the get_job_logs() …

[yaobaiwei]

What this PR does / why we need it:

In the get_job_logs() func of the newly unified Training Client of python sdk, as the return type of get_job_pod_names() is [str] now, no metadata attr for log anymore.

A careless bug I believe, just found it when I was testing my own proj.

Which issue(s) this PR fixes (optional, in Fixes #<issue number>, #<issue number>, ... format, will close the issue(s) when PR gets merged):
Fixes #

Checklist:

• Docs included if any changes are user facing

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[andreyvelich]

Thank you for your contribution and fixing this @yaobaiwei!
Please sign the CLA
/lgtm

[coveralls]

Pull Request Test Coverage Report for Build 4196610894

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.03%) to 39.356%

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Totals
Change from base Build 4193123906:	0.03%
Covered Lines:	2725
Relevant Lines:	6924

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💛 - Coveralls

[johnugeorge]

Thanks @yaobaiwei

/approve

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[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: andreyvelich, johnugeorge, yaobaiwei

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