Buildfarm animal caiman showing a plperl test issue with newer Perl versions

Hello hackers,

As recent caiman failures ([1], [2], ...) show, plperl.sql is incompatible
with Perl 5.40. (The last successful test runs took place when cayman
had Perl 5.38.2 installed: [3].)

FWIW, I've found an already-existing fix for the issue [4] and a note
describing the change for Perl 5.39.10 [5].

[1] https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=caiman&dt=2024-06-24%2001%3A34%3A23
[2] https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=caiman&dt=2024-06-24%2000%3A15%3A16
[3] https://buildfarm.postgresql.org/cgi-bin/show_log.pl?nm=caiman&dt=2024-05-02%2021%3A57%3A17
[4] 

https://git.alpinelinux.org/aports/tree/community/postgresql14/fix-test-plperl-5.8-pragma.patch?id=28aeb872811f59a7f646aa29ed7c9dc30e698e65
[5] https://metacpan.org/release/PEVANS/perl-5.39.10/changes#Selected-Bug-Fixes

Best regards,
Alexander