Allow disabling the search for tags fallback

[JAVGan]

When searching for the image existence, by defaut, the library first search it from its name and if not found by the tags. However, there are certain situations which the latter search (tags) may not be executed.

This commit preserves the default experience of the library while allowing to disable the tags search fallback wheenver the new publishing metadata attribute search_tags is set to False.

Refers to SPSTRAT-451

[JAVGan]

@lslebodn @jajreidy @rohanpm PTAL

[rohanpm]

I'm a little uneasy with this change. Ultimately I'll release it if you want, as at the end of the day it's just taking a feature you've added and making it optional, and I wouldn't have objected if it had been implemented that way in the first place.

However this does feel a bit like there's a flaw in the way the data is being managed, and rather than addressing it you're adding a flag which can be optionally used to work around the problem.

No explanation is given of the scenarios where a caller should pass search_tags=True and where they should pass search_tags=False. Can you easily explain when the caller might want to do one or the other? Are you sure there's even a way to programmatically make that decision?

In other words, when you said we can add the option "False" in our tooling for this particular case, what exactly is "this particular case"? And if it's OK to disable searching by tag in that case, why isn't it OK to disable it in all cases - i.e. why is the feature needed at all.

[JAVGan]

@rohanpm The search for tags feature is important for the Stratosphere workflow and I initially thought that I could avoid it for the community workflow in order to solve a bug, but actually that won't be necessary.

I agree this change is not ideal for the upstream library so I'm going to close it.

I've talked with Lukas and we can pass an additional tag to the community workflow to avoid the issue, but the problem is that we desire to avoid adding it to the S3 object. I'll open a new MR to allow adding custom tags just for snapshots/amis and the problem will be solved, without having to use this PR's alternative which seems to be ugly.

Thanks for the review and let's keep the search for tags as it is.