In #86163 we added a check on the branch name to avoid running the
tooling on stable branches, however this check used bash-specific
syntax. While the hashbang in the pre-commit hook specifies that the
hook should be run using bash, we were using the npm module "husky" to
manage git hooks, which would ignore this hashbang and always run the
hook using sh, causing the hook to fail in all cases.

After some consideration, we have decided to stop using husky, as its
main purpose is to make hook management easier in npm-based projects.
Since we already need a script to enable the tooling, we can do
essentially the same thing that husky is doing but with more control
over the process with no drawbacks.

closes odoo/odoo#86888

Signed-off-by: Simon Genin (ges@odoo) <ges@odoo.com>