announce the NumPy 2.2.1 release (#810)

Author: charris

content/en/news.md

@@ -442,6 +442,7 @@ Here is a list of NumPy releases, with links to release notes. Bugfix
 releases (only the `z` changes in the `x.y.z` version number) have no new
 features; minor releases (the `y` increases) do.
 
+- NumPy 2.2.1 ([release notes](https://github.com/numpy/numpy/releases/tag/v2.2.1)) -- _21 Dec 2024_.
 - NumPy 2.2.0 ([release notes](https://github.com/numpy/numpy/releases/tag/v2.2.0)) -- _8 Dec 2024_.
 - NumPy 2.1.3 ([release notes](https://github.com/numpy/numpy/releases/tag/v2.1.3)) -- _2 Nov 2024_.
 - NumPy 2.1.2 ([release notes](https://github.com/numpy/numpy/releases/tag/v2.1.2)) -- _5 Oct 2024_.