docs: lock sphinx and fix toctree (nextcord#827)

sphinx-doc/sphinx#10807 decided to add a feature which was enabled by default.
This feature however increased the toctree's height and width by a huge amount - a breaking change.
This locks sphinx to an exact version to reduce issues like this again.

docs/conf.py

@@ -358,6 +358,11 @@
 # texinfo_no_detailmenu = False
 
 
+# Remove members from toctree, added by sphinx 5.2
+# This *could* be re-enabled once the docs uses multiple pages.
+toc_object_entries = False
+
+
 def setup(app):
     if app.config.language == "ja":
         app.config.intersphinx_mapping["py"] = ("https://docs.python.org/ja/3", None)

setup.py

@@ -44,7 +44,7 @@
 extras_require = {
     "voice": ["PyNaCl>=1.3.0,<1.5"],
     "docs": [
-        "sphinx>=5.0.1,<6",
+        "sphinx==5.2.3",
         "sphinxcontrib_trio==1.1.2",
         "sphinxcontrib-websupport",
         "typing_extensions>=4.2.0, <5",