fix(comparators/utils/compare): do not return early after checking only content

Commit 5b187ad5 introduces a regression by
unconditionally returning too early when files are identical contentwise. A
configured check for diffs in metadata would be skipped.

Instead of returning early, we bypass the specialize() call in compare_files
for binary identical files through an if-else, such that metadata checks can
still be run if required.

Closes #411

Co-authored-by: kryggird <43894260+kryggird@users.noreply.github.com>
Co-authored-by: Max Albrecht <1@178.is>
Co-authored-by: Joel Cantillo <joel.cantillo@proton.me>