Update ruamel.yaml from pin to bounds

This achieves two things. First, it gets us onto the latest version
(as of today), and second it resolves any complaint that the pin is
too restrictive for users.

Author: sirosen

CHANGELOG.rst

@@ -14,6 +14,8 @@ Unreleased
 - Update the ``gitlab`` and ``renovate`` hooks to use
   ``--regex-variant nonunicode``. Thanks :user:`quentin-ag` and :user:`Callek`
   for reporting! (:issue:`516`, :issue:`518`)
+- Update the required ``ruamel.yaml`` version to a range,
+  ``>=0.18.10,<0.19.0``.
 
 0.31.0
 ------

pyproject.toml

@@ -18,7 +18,7 @@ classifiers = [
 requires-python = ">=3.9"
 dependencies = [
     'tomli>=2.0;python_version<"3.11"',
-    "ruamel.yaml==0.18.7",
+    "ruamel.yaml>=0.18.10,<0.19.0",
     "jsonschema>=4.18.0,<5.0",
     "regress>=2024.11.1",
     "requests<3.0",