Merge pull request #4115 from Unidata/dependabot-pip-ci-traitlets-5.16.0

CI: (deps): Bump traitlets from 5.15.1 to 5.16.0 in /ci

Author: dopplershift

ci/requirements.txt

@@ -5,5 +5,5 @@ pooch==1.9.0
 pint==0.25.3
 pyproj==3.7.2
 scipy==1.17.1
-traitlets==5.15.1
+traitlets==5.16.0
 xarray==2025.10.1