Bump urllib3 from 2.5.0 to 2.6.3 in /requirements/docs (kurtmckee#544)

Author: kurtmckee

requirements/docs/requirements.txt

@@ -22,4 +22,4 @@ sphinxcontrib-jsmath==1.0.1 ; python_version >= "3.10"
 sphinxcontrib-qthelp==2.0.0 ; python_version >= "3.10"
 sphinxcontrib-serializinghtml==2.0.0 ; python_version >= "3.10"
 tomli==2.2.1 ; python_version == "3.10"
-urllib3==2.5.0 ; python_version >= "3.10"
+urllib3==2.6.3 ; python_version >= "3.10"