Provide fallback to Python/Spark-like splitting in splitBy*() functions

[rschu1ze]

Added a setting splitby_max_substrings_includes_remaining_string which controls if functions splitBy*() with max_substring argument > 0 include the remaining string in the result array (Python/Spark semantics) or not. To keep existing use cases working, I did not touch the default behavior, i.e. splitby_max_substrings_includes_remaining_string by default is 0.

For reference, please see the discussions

• after Add optional max_tokens argument for function splitByRegexp #42673 (comment) and
• after Docs: Mention behavior change of splitByChar() in v22.11 #54484 (comment)

Changelog category (leave one):

• Improvement

Changelog entry (a user-readable short description of the changes that goes to CHANGELOG.md):

Added a setting "splitby_max_substrings_includes_remaining_string" which controls if functions "splitBy*()" with argument "max_substring" > 0 include the remaining string (if any) in the result array (Python/Spark semantics) or not. The default behavior does not change.

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[antonio2368]

we can probably use the compatibility setting to set it to correct behaviour and mention here that it can be used also.

[rschu1ze]

Will check.

[rschu1ze]

The new behavior with splitby_max_substrings_includes_remaining_string = 1 doesn't match 100% the pre-v22.11 behavior (one needs to adjust max_substrings argument by 1). But I feel that's an acceptable compromise which reduces implementation complexity and understanding for users. So I better refrain from compatibility settings, to keep surprises minimal.

[antonio2368]

similar chunk seems to be repeated often

[rschu1ze]

This will hopefully become simpler.

[rschu1ze]

There are some subtle differences between places where the chunk is used. Can't pull it out easily. It is much simpler in the last commit, guess we can keep it as is.