update python packages for doc generation following recent evolution in

the default sphinx version on read the docs.

doc/python_requirements.txt

@@ -6,10 +6,11 @@
 # python -m pip install -r python-requirements.txt
 
 wheel>=0.38.4 # help forward compatibility for pip with old sphinx plugins
-sphinx==4.5.0
-sphinx_rtd_theme==1.1.1
+sphinx==5.3.0
+sphinx_rtd_theme==1.3.0
 sphinx_git==11.0.0
 breathe==4.34.0
-exhale==0.3.6
+exhale==0.3.7
 m2r2==0.3.2
 sphinx-copybutton==0.5.2
+#sphinxcontrib-applehelp==1.0.7