You don't even need Time::Local,

my $yesterday= do {
    my($y,$m,$d)= (localtime(
        time-60*60*(12+(localtime)[2]) ))[5,4,3];
    sprintf "%04d-%02d-%02d", 1900+$y, 1+$m, $d;
};
[download]

or, just for fun:

my $yesterday= join"-",mapcar{sprintf "%0".shift()."d",pop()+pop()}
[4,2,2],[(localtime(
time-60*60*(12+(localtime)[2]) ))[5,4,3]],[1900,1,0];
[download]

        - tye (but my friends call me "Tye")