The `# -*- coding: utf-8 -*-` headers were useful for Python 2, and
aren't needed for Python 3 where UTF-8 is the default.
yamllint support of Python 2 was dropped in early 2021, see commit
a3fc64d "End support for Python 2".
Let's drop these headers.
We'd like to disallow brackets and braces in our YAML, but there's a
catch: the only way to describe an empty array or hash in YAML is to
supply an empty one (`[]` or `{}`). Otherwise, the value will be null.
This commit adds a `non-empty` option to `forbid` for brackets and
braces. When it is set, all flow and sequence mappings will cause errors
_except_ for empty ones.
Add 'forbid' configuration parameters to the braces and brackets rules
to allow users to forbid the use of flow style collections, flow
mappings and flow sequences.
Adrien Vergé
Rusty Geldmacher
Satoru SATOH
Jim Riggs