Fix pyproject.toml tools -> tool. (#1020)

* Fix pyproject.toml tools -> tool.

* Update changelog.

Author: bdice

changelog.txt

@@ -7,13 +7,14 @@ The **signac** package follows `semantic versioning <https://semver.org/>`_.
 Version 2
 =========
 
-[2.2.1] -- 2024-xx-xx
+[2.2.1] -- 2025-xx-xx
 ---------------------
 
 Fixed
 +++++
 
  - Support for Numpy 2.0 in tests (#997).
+ - Use ``tool.setuptools`` key in ``pyproject.toml`` (#1020).
 
 [2.2.0] -- 2024-02-13
 ---------------------

pyproject.toml

@@ -55,7 +55,7 @@ Download = "https://pypi.org/project/signac/"
 Source = "https://github.com/glotzerlab/signac"
 Issues = "https://github.com/glotzerlab/signac/issues"
 
-[tools.setuptools.packages.find]
+[tool.setuptools.packages.find]
 namespaces = false
 exclude = ["tests*", "benchmarks*"]