[perl #130517] [LTA] .max should warn if it sees useless :by parameter ( .max(:by(*.value)) )

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# New Ticket Created by  Aleks-Daniel Jakimenko-Aleksejev 
# Please include the string:  [perl #130517]
# in the subject line of all future correspondence about this issue. 
# <URL: https://rt.perl.org/Ticket/Display.html?id=130517 >


Code:
say { 0 => 1, 1 => 0 }.max(:by(*.value))

Result:
1 => 0


Code:
say { 0 => 1, 1 => 0 }.max(*.value)

Result:
0 => 1


I think :by(…) is something people commonly try (somebody did this on camelia, 
and I remember doing this myself), so it would be great if it could warn the 
user.