It's really not very clear what you want to do.

Here's one possible solution.

#!/usr/bin/perl

use strict;
use warnings;

use Data::Dumper;

my %hash = (list => { find => [ {type => 'error', column => 106 },
                                {type => 'warning', column => 1 } ] } 
+);

print Dumper \%hash;

pop @{$hash{list}{find}};

print Dumper \%hash;
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