Added new function JSONExtractArrayRaw

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• New Feature

Changelog entry (up to few sentences, required except for Non-significant/Documentation categories):
Added function JSONExtractArrayRaw

Detailed description (optional):

Added new function JSONExtractArrayRaw. This function will return an array on unparsed json array elements.

Combined with arrayJoin this function can be useful when you need to "flatten" nested json (for example with Kafka engine)

example:

SELECT arrayJoin(JSONExtractArrayRaw('{"a": 1, "b": [{"c": 100}, {"d": 200}]}', 'b'))

┌─arrayJoin(JSONExtractArrayRaw('{"a": 1, "b": [{"c": 100}, {"c": 200}]}', 'b'))─┐
│ {"c":100}                                                                      │
│ {"c":200}                                                                      │
└──────────────────────────────────────────────────────────────