shrink or resize arraylist in readUntilDelimiterArrayList

[mjoud]

The use of array_list.shrink(0) in Reader.readUntilDelimiterArrayList could potentially be expensive (admittedly untested):

zig/lib/std/io/reader.zig

Line 101 in d907f57

array_list.shrink(0);

Should array_list.resize(0) be used instead?