List changelogs is broken in version 2.5.4 on macos

[himito]

Hi,

when I run

git-quick-stats -L

I receive

    date: illegal option -- d
    usage: date [-jnRu] [-I[date|hours|minutes|seconds]] [-f input_fmt]
    [-r filename|seconds] [-v[+|-]val[y|m|w|d|H|M|S]]
    [[[[mm]dd]HH]MM[[cc]yy][.SS] | new_date] [+output_fmt]

It's related to #152, and I think that is the following line:

https://github.com/arzzen/git-quick-stats/blob/7b1e0b2a65e9ecaa8a166d855028f223b563aa00/git-quick-stats#L419