chore: update sphinx version

Sphinx version error:
The sphinxcontrib.applehelp extension used by this project needs at least Sphinx v5.0; it therefore cannot be built with this version.
make: *** [Makefile:20: html] Error 2

Requirement already satisfied: sphinxcontrib-applehelp in /usr/local/lib/python3.12/site-packages (from sphinx<5,>=4.5.0->-r user_guide_src/requirements.txt (line 1)) (1.0.8)

Author: kenjis

user_guide_src/requirements.txt

@@ -1,5 +1,5 @@
-sphinx>=4.5.0,<5
+sphinx>=5.0.0,<6
 sphinxcontrib-phpdomain>=0.8.0
 docutils>=0.16
 sphinx-rtd-theme>=0.5.0
-jinja2<3.1
+jinja2>=3.1.3