Python 3.13 is the current version and was released over a month ago
(see https://devguide.python.org/versions). The dependencies we use now
support Python 3.13, most importantly `fonttools` which uses OS-specific
builds and for which compatibility got introduced in
https://github.com/fonttools/fonttools/pull/3656 and the corresponding
`cp313` wheels for all distributions are published on
https://pypi.org/project/fonttools/#files.
Moreover, we fix forgotten `npx` usage in the font tests README which
was encountered while testing this patch.
I noticed the following warning in the GitHub Actions workflow logs:
`Configuration file not found: .github/linter_config.yml`
The configuration file is called `fluent_linter_config.yml` instead, so
this commit fixes the path so it points to the correct file.
Fixes 487816b.
The current stable version of Python is Python 3.12, see
https://www.python.org/downloads, so we should switch to that since
Python 3.10 is older and only receives security updates.
This commit tweaks the Fluent linter workflow to match the other
workflow files we have, so we make sure the steps have a newline between
them for better readability and align names and descriptions of steps
with how they are called in the other workflow files we have.
