Preparations for fd 9 release

[sharkdp]

Release checklist

This file can be used as-is, or copied into the GitHub PR description which includes
necessary changes for the upcoming release.

Version bump

• Create a new branch for the required changes for this release.
• Update version in Cargo.toml. Run cargo build to update Cargo.lock.
  Make sure to git add the Cargo.lock changes as well.
• Find the current min. supported Rust version by running
  grep rust-version Cargo.toml.
• Update the fd version and the min. supported Rust version in README.md.
• Update CHANGELOG.md. Change the heading of the "Upcoming release" section
  to the version of this release.

Pre-release checks and updates

• Install the latest version (cargo install --locked -f --path .) and make
  sure that it is available on the PATH (fd --version should show the
  new version).
• Review -h, --help, and the man page.
• Run fd -h and copy the output to the "Command-line options" section in
  the README
• Push all changes and wait for CI to succeed (before continuing with the
  next section).
• Optional: manually test the new features and command-line options described
  in the CHANGELOG.md.
• Run cargo publish --dry-run to make sure that it will succeed later
  (after creating the GitHub release).

Release

• Merge your release branch (should be a fast-forward merge).
• Create a tag and push it: git tag vX.Y.Z; git push origin tag vX.Y.Z.
  This will trigger the deployment via GitHub Actions.
  REMINDER: If your origin is a fork, don't forget to push to e.g. upstream
  instead.
• Go to https://github.com/sharkdp/fd/releases/new to create the new
  release. Select the new tag and also use it as the release title. For the
  release notes, copy the corresponding section from CHANGELOG.md and
  possibly add additional remarks for package maintainers.
  Publish the release.
• Check if the binary deployment works (archives and Debian packages should
  appear when the CI run for the Git tag has finished).
• Publish to crates.io by running cargo publish in a clean repository.
  One way to do this is to clone a fresh copy.

Post-release

• Prepare a new "Upcoming release" section at the top of CHANGELOG.md.
  Put this at the top:

  # Upcoming release
  
  ## Features
  
  
  ## Bugfixes
  
  
  ## Changes
  
  
  ## Other