[Issue 13717] `split` no longer defined by std.string

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=13717

--- Comment #8 from Илья Ярошенко <ilyayaroshenko at gmail.com> ---
And we can not deprecate them too because there is now deprecation for imports
;-(

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