chore: fix sphinxcontrib-applehelp 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)

user_guide_src/requirements.txt

@@ -1,5 +1,6 @@
 sphinx>=4.5.0,<5
 sphinxcontrib-phpdomain>=0.8.0
+sphinxcontrib-applehelp>=1.0.4,<1.0.8
 docutils>=0.16
 sphinx-rtd-theme>=0.5.0
 jinja2<3.1