rust: Upgrade to format-bytes 0.3
This removes use of the proc-macro-hack crate, which is possible now that
we don’t support Rust 1.41 to 1.44 anymore.
This in turn fixes spurious errors reported by rust-analyser:
https://github.com/rust-analyzer/rust-analyzer/issues/9606#issuecomment-
919240134
Differential Revision: https://phab.mercurial-scm.org/D11938
lib - sys sys
mercurial - sys sys
hgrc.d - sys sys
9diff.rc - sys sys
factotum.rc - sys sys
rc - sys sys
bin - sys sys
9diff - sys sys
hg - sys sys
sys - sys sys
lib - sys sys
python - sys sys
lib - sys sys
python2.5 - sys sys
site-packages - sys sys
hgext - sys sys
+ - sys sys
mercurial - sys sys
+ - sys sys
mercurial-VERSION-py2.5.egg-info - sys sys
src - sys sys
cmd - sys sys
hg - sys sys
+ - sys sys