#20 Impelement ArrayMerge sniff in foreach

[larsroettig]

Implementation for #20

Currently we have many findings in 2.3 develop

bin/phpcs --standard=Magento2 --sniffs=Magento2.Performance.ForeachArrayMerge  app/code app/lib

Magento 2 findings with current Implementation

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A TOTAL OF 0 ERRORS AND 280 WARNINGS WERE FOUND IN 212 FILES
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[lenaorobei]

I checked some findings and they look false-positive to me. Probably, they require serious code refactoring, not just moving array_merge outside the loop.
Need more thoughts here to understand if we really want to warn developers about any case of usage array_merge inside the loop.

[buskamuza]

We should accept it, but include explanation of how to fix the problematic code. Think about a catalog of recommendations (either here in wiki or in devdocs).

[orlangur]

@larsroettig @buskamuza

A TOTAL OF 0 ERRORS AND 280 WARNINGS WERE FOUND IN 212 FILES

So how this rule can be useful?