chore: support sphinx 8 (#2011)

Support Sphinx's latest version.

docs/readthedocs.txt

@@ -1,38 +1,34 @@
 alabaster==0.7.13 ; python_version >= "3.8" and python_version < "3.9"
-alabaster==0.7.16 ; python_version >= "3.9" and python_version < "4.0"
-anyio==4.4.0 ; python_version >= "3.9" and python_version < "3.13"
+alabaster==0.7.16 ; python_version >= "3.9" and python_version < "3.10"
+alabaster==1.0.0 ; python_version >= "3.10" and python_version < "4.0"
 babel==2.16.0 ; python_version >= "3.8" and python_version < "4.0"
 beautifulsoup4==4.12.3 ; python_version >= "3.8" and python_version < "4.0"
-certifi==2024.7.4 ; python_version >= "3.8" and python_version < "4.0"
+certifi==2024.8.30 ; python_version >= "3.8" and python_version < "4.0"
 charset-normalizer==3.3.2 ; python_version >= "3.8" and python_version < "4.0"
-click==8.1.7 ; python_version >= "3.9" and python_version < "3.13"
-colorama==0.4.6 ; python_version >= "3.8" and python_version < "4.0" and (python_version < "3.13" or sys_platform == "win32")
+colorama==0.4.6 ; python_version >= "3.8" and python_version < "4.0"
 docutils==0.20.1 ; python_version >= "3.8" and python_version < "3.9"
 docutils==0.21.2 ; python_version >= "3.9" and python_version < "4.0"
-exceptiongroup==1.2.2 ; python_version >= "3.9" and python_version < "3.11"
-h11==0.14.0 ; python_version >= "3.9" and python_version < "3.13"
-idna==3.7 ; python_version >= "3.8" and python_version < "4.0"
+idna==3.10 ; python_version >= "3.8" and python_version < "4.0"
 imagesize==1.4.1 ; python_version >= "3.8" and python_version < "4.0"
-importlib-metadata==8.4.0 ; python_version >= "3.8" and python_version < "3.10"
+importlib-metadata==8.5.0 ; python_version >= "3.8" and python_version < "3.10"
 jinja2==3.1.4 ; python_version >= "3.8" and python_version < "4.0"
-livereload==2.7.0 ; python_version >= "3.8" and python_version < "3.9"
+livereload==2.7.0 ; python_version >= "3.8" and python_version < "4.0"
 markupsafe==2.1.5 ; python_version >= "3.8" and python_version < "4.0"
 packaging==24.1 ; python_version >= "3.8" and python_version < "4.0"
 pygments==2.18.0 ; python_version >= "3.8" and python_version < "4.0"
 python-dotenv==1.0.1 ; python_version >= "3.8" and python_version < "4.0"
-pytz==2024.1 ; python_version >= "3.8" and python_version < "3.9"
+pytz==2024.2 ; python_version >= "3.8" and python_version < "3.9"
 requests==2.32.3 ; python_version >= "3.8" and python_version < "4.0"
-sniffio==1.3.1 ; python_version >= "3.9" and python_version < "3.13"
 snowballstemmer==2.2.0 ; python_version >= "3.8" and python_version < "4.0"
 soupsieve==2.6 ; python_version >= "3.8" and python_version < "4.0"
-sphinx-autobuild==2021.3.14 ; python_version >= "3.8" and python_version < "3.9"
-sphinx-autobuild==2024.4.16 ; python_version >= "3.9" and python_version < "3.13"
+sphinx-autobuild==2021.3.14 ; python_version >= "3.8" and python_version < "4.0"
 sphinx-design==0.5.0 ; python_version >= "3.8" and python_version < "3.9"
 sphinx-design==0.6.1 ; python_version >= "3.9" and python_version < "3.13"
-sphinx-docsearch==0.0.7 ; python_version >= "3.8" and python_version < "4.0"
+sphinx-docsearch==0.1.0 ; python_version >= "3.8" and python_version < "4.0"
 sphinx-sitemap==2.6.0 ; python_version >= "3.8" and python_version < "4.0"
 sphinx==7.1.2 ; python_version >= "3.8" and python_version < "3.9"
-sphinx==7.3.7 ; python_version >= "3.9" and python_version < "4.0"
+sphinx==7.4.7 ; python_version >= "3.9" and python_version < "3.10"
+sphinx==8.0.2 ; python_version >= "3.10" and python_version < "4.0"
 sphinxcontrib-applehelp==1.0.4 ; python_version >= "3.8" and python_version < "3.9"
 sphinxcontrib-applehelp==2.0.0 ; python_version >= "3.9" and python_version < "4.0"
 sphinxcontrib-devhelp==1.0.2 ; python_version >= "3.8" and python_version < "3.9"
@@ -44,12 +40,7 @@ sphinxcontrib-qthelp==1.0.3 ; python_version >= "3.8" and python_version < "3.9"
 sphinxcontrib-qthelp==2.0.0 ; python_version >= "3.9" and python_version < "4.0"
 sphinxcontrib-serializinghtml==1.1.5 ; python_version >= "3.8" and python_version < "3.9"
 sphinxcontrib-serializinghtml==2.0.0 ; python_version >= "3.9" and python_version < "4.0"
-starlette==0.38.2 ; python_version >= "3.9" and python_version < "3.13"
-tomli==2.0.1 ; python_version >= "3.9" and python_version < "3.11"
-tornado==6.4.1 ; python_version >= "3.8" and python_version < "3.9"
-typing-extensions==4.12.2 ; python_version >= "3.9" and python_version < "3.11"
-urllib3==2.2.2 ; python_version >= "3.8" and python_version < "4.0"
-uvicorn==0.30.6 ; python_version >= "3.9" and python_version < "3.13"
-watchfiles==0.23.0 ; python_version >= "3.9" and python_version < "3.13"
-websockets==13.0 ; python_version >= "3.9" and python_version < "3.13"
-zipp==3.20.0 ; python_version >= "3.8" and python_version < "3.10"
+tomli==2.0.2 ; python_version >= "3.9" and python_version < "3.11"
+tornado==6.4.1 ; python_version >= "3.8" and python_version < "4.0"
+urllib3==2.2.3 ; python_version >= "3.8" and python_version < "4.0"
+zipp==3.20.2 ; python_version >= "3.8" and python_version < "3.10"