znapzend broken

[infinisil]

Issue description

Znapzend throws an error when ran in latest master (405f9d1):

$ znapzend
perl: warning: Setting locale failed.
perl: warning: Please check that your locale settings:
        LANGUAGE = (unset),
        LC_ALL = (unset),
        LANG = "en_US.UTF-8"
    are supported and installed on your system.
perl: warning: Falling back to the standard locale ("C").
"slurp" is not exported by the Mojo::Util module
Can't continue after import errors at /nix/store/pxc4h5vchr0z9zqnqg4r9ladny34lpp6-znapzend-0.18.0/lib/ZnapZend.pm line 5.
BEGIN failed--compilation aborted at /nix/store/pxc4h5vchr0z9zqnqg4r9ladny34lpp6-znapzend-0.18.0/lib/ZnapZend.pm line 5.
Compilation failed in require at result/bin/znapzend line 9.
BEGIN failed--compilation aborted at result/bin/znapzend line 9.

This was introduced in 3c74f80 and because @r-ryantm apparently doesn't run the most important znapzend command, the error wasn't caught in #39029 either.

Reverting the update of Mojolicious in the above commit makes it work again. I don't have any experience with Perl, so I'm not sure what's the best course of action to fix this.

Ping @volth @otwieracz @ryantm @fpletz

[ryantm]

It almost certainly tried to run it and since it didn't get a non-zero exit code, or a help message, it didn't comment on it. I'll add an issue to warn about binaries that return non-zero exit codes; we will see if that gets annoying, since nixpkgs-update doesn't really know how to run specific binaries.