Bump Sphinx to V5 to fix build.

Author: brunns

.readthedocs.yml

@@ -5,7 +5,7 @@ build:
   os: ubuntu-22.04
   tools:
     # Keep version in sync with tox.ini (docs and gh-actions).
-    python: "3.11"
+    python: "3.12"
 
 sphinx:
   configuration: doc/conf.py

pyproject.toml

@@ -46,7 +46,7 @@ classifiers = [
 dynamic = ["version"]
 
 [project.optional-dependencies]
-docs = ["sphinx~=4.0", "alabaster~=0.7"]
+docs = ["sphinx~=5.0", "alabaster~=0.7"]
 tests = [
   "pytest>=5.0",
   "pytest-sugar",

tox.ini

@@ -16,8 +16,8 @@ python =
     3.8: py38, py38-numpy
     3.9: py39, py39-numpy
     3.10: py310, py310-numpy
-    3.11: py311, py311-numpy, typing, manifest, docs
-    3.12: py312, py312-numpy, lint, changelog
+    3.11: py311, py311-numpy
+    3.12: py312, py312-numpy, lint, changelog, typing, manifest, docs
     pypy-2: pypy2
     pypy-3: pypy3
 
@@ -137,14 +137,14 @@ commands =
 
 [testenv:docs]
 # Keep basepython in sync with gh-actions and .readthedocs.yml.
-basepython = python3.11
+basepython = python3.12
 extras = docs
 commands =
     sphinx-build -n -T -b html -d {envtmpdir}/doctrees doc doc/_build/html
 
 
 [testenv:manifest]
-basepython = python3.11
+basepython = python3.12
 deps =
     check-manifest
     setuptools-scm
@@ -173,7 +173,7 @@ commands = towncrier --draft
 
 
 [testenv:typing]
-basepython = python3.11
+basepython = python3.12
 deps =
     mypy
     types-mock