(#417) - Make the "cargo fmt" lint step in CI a manual process

#417
7 jobs from master in 1 minute and 29 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Test
canceled #222562
fedora test

00:01:29

 
  Lint
canceled #222564
allowed to fail manual
clippy

canceled #222563
allowed to fail manual
rustfmt

canceled #222565
tarball

 
  Cross Distro
canceled #222568
debian_i386:testing

canceled #222567
debian:testing

canceled #222566
fedora:rawhide