whatsnew entry

Author: bjlittle

docs/src/whatsnew/latest.rst

@@ -288,6 +288,9 @@ This document explains the changes made to Iris for this release
 #. `@wjbenfold`_ fixed tests for hybrid formulae that weren't being found by
    nose (:issue:`4431`, :pull:`4450`)
 
+#. `@bjlittle`_ adopted GitHub Actions for continuous integration.
+   (:pull:`4503`)
+
 .. comment
     Whatsnew author names (@github name) in alphabetical order. Note that,
     core dev names are automatically included by the common_links.inc:
@@ -307,4 +310,4 @@ This document explains the changes made to Iris for this release
 .. _UGRID: http://ugrid-conventions.github.io/ugrid-conventions/
 .. _sort-all: https://github.com/aio-libs/sort-all
 .. _faster documentation building: https://docs.readthedocs.io/en/stable/guides/conda.html#making-builds-faster-with-mamba
-.. _Metarelate: http://www.metarelate.net/
+.. _Metarelate: http://www.metarelate.net/