[BEAM-13329][Playground] Add new api method to get logs of code processing

[AydarZaynutdinov]

[BEAM-13329]
Add a new API method to get logs of the code processing

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ValidatesRunner compliance status (on master branch)

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Examples testing status on various runners

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Post-Commit SDK/Transform Integration Tests Status (on master branch)

Go	Java	Python

Pre-Commit Tests Status (on master branch)

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[AydarZaynutdinov]

R: @pabloem

[pabloem]

this LGTM. Just a question: I see we're setting the logs index to 0 - but where are we storing existing logs? (I guess we're not doing that yet?)

[AydarZaynutdinov]

this LGTM. Just a question: I see we're setting the logs index to 0 - but where are we storing existing logs? (I guess we're not doing that yet?)

Yes, PR with storing logs will be the next one.