Replace isort, flake8, pycln and pyupgrade by ruff. [Ruff](https://github.com/charliermarsh/ruff) is getting popular lately, and I really like the idea of having a single tool for Python lining instead of N which currently exist. Also written in Rust which is a good use case for this.

 It's supposed to have equivalent functionality, to the ones we are using. The fact that major projects are adopting it is a good sign (see list in their readme).  There are also a few extra options in their readme that look interesting and that we could enable (without having to install yet another plugin)

We won't gain much speed-wise: previously isort, flake8 (which itself is an abstraction over pycodestyle and pyflakes), pycln and pyupgrade  on all files was around 1s, and now it's 20ms. But with mypy taking 10s, it makes mostly no difference.
Still it makes the overall linting configuration easier to maintain.


If we go forward with this, I imagine a changelog is not needed? 

#!/bin/sh
#
# An example hook script to prepare the commit log message.
# Called by "git commit" with the name of the file that has the
# commit message, followed by the description of the commit
# message's source.  The hook's purpose is to edit the commit
# message file.  If the hook fails with a non-zero status,
# the commit is aborted.
#
# To enable this hook, rename this file to "prepare-commit-msg".

# This hook includes three examples. The first one removes the
# "# Please enter the commit message..." help message.
#
# The second includes the output of "git diff --name-status -r"
# into the message, just before the "git status" output.  It is
# commented because it doesn't cope with --amend or with squashed
# commits.
#
# The third example adds a Signed-off-by line to the message, that can
# still be edited.  This is rarely a good idea.

COMMIT_MSG_FILE=$1
COMMIT_SOURCE=$2
SHA1=$3

/usr/bin/perl -i.bak -ne 'print unless(m/^. Please enter the commit message/..m/^#$/)' "$COMMIT_MSG_FILE"

# case "$COMMIT_SOURCE,$SHA1" in
#  ,|template,)
#    /usr/bin/perl -i.bak -pe '
#       print "\n" . `git diff --cached --name-status -r`
# 	 if /^#/ && $first++ == 0' "$COMMIT_MSG_FILE" ;;
#  *) ;;
# esac

# SOB=$(git var GIT_COMMITTER_IDENT | sed -n 's/^\(.*>\).*$/Signed-off-by: \1/p')
# git interpret-trailers --in-place --trailer "$SOB" "$COMMIT_MSG_FILE"
# if test -z "$COMMIT_SOURCE"
# then
#   /usr/bin/perl -i.bak -pe 'print "\n" if !$first_line++' "$COMMIT_MSG_FILE"
# fi

#!/bin/sh
#
# An example hook script to prepare the commit log message.
# Called by "git commit" with the name of the file that has the
# commit message, followed by the description of the commit
# message's source.  The hook's purpose is to edit the commit
# message file.  If the hook fails with a non-zero status,
# the commit is aborted.
#
# To enable this hook, rename this file to "prepare-commit-msg".

# This hook includes three examples. The first one removes the
# "# Please enter the commit message..." help message.
#
# The second includes the output of "git diff --name-status -r"
# into the message, just before the "git status" output.  It is
# commented because it doesn't cope with --amend or with squashed
# commits.
#
# The third example adds a Signed-off-by line to the message, that can
# still be edited.  This is rarely a good idea.

COMMIT_MSG_FILE=$1
COMMIT_SOURCE=$2
SHA1=$3

/usr/bin/perl -i.bak -ne 'print unless(m/^. Please enter the commit message/..m/^#$/)' "$COMMIT_MSG_FILE"

# case "$COMMIT_SOURCE,$SHA1" in
#  ,|template,)
#    /usr/bin/perl -i.bak -pe '
#       print "\n" . `git diff --cached --name-status -r`
# 	 if /^#/ && $first++ == 0' "$COMMIT_MSG_FILE" ;;
#  *) ;;
# esac

# SOB=$(git var GIT_COMMITTER_IDENT | sed -n 's/^\(.*>\).*$/Signed-off-by: \1/p')
# git interpret-trailers --in-place --trailer "$SOB" "$COMMIT_MSG_FILE"
# if test -z "$COMMIT_SOURCE"
# then
#   /usr/bin/perl -i.bak -pe 'print "\n" if !$first_line++' "$COMMIT_MSG_FILE"
# fi
