[doc] Use Sphinx >= 6.2.1

Update requirements.txt and basepython.
Python 3.8 is needed for Sphinx >= 6.2.

Bug: T333816
Change-Id: Ic03eabb960b1581660cfff7d7cc8f92634d0a155
---
M docs/conf.py
M docs/requirements.txt
M tox.ini
3 files changed, 22 insertions(+), 9 deletions(-)

diff --git a/docs/conf.py b/docs/conf.py
index d1fb603..42e9e44 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -1,6 +1,6 @@
 """Configuration file for Sphinx."""
 #
-# (C) Pywikibot team, 2014-2022
+# (C) Pywikibot team, 2014-2023
 #
 # Distributed under the terms of the MIT license.
 #
@@ -43,7 +43,7 @@
 
 # If your documentation needs a minimal Sphinx version, state it here.
 #
-needs_sphinx = '5.2.3'
+needs_sphinx = '6.2.1'
 
 # Add any Sphinx extension module names here, as strings. They can be
 # extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
diff --git a/docs/requirements.txt b/docs/requirements.txt
index 6282682..c16dfa7 100644
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -1,6 +1,6 @@
 # This is a PIP requirements file for building Sphinx documentation of pywikibot
 # requirements.txt is also needed
-sphinx >= 5.2.3
-rstcheck >=6.1.0
-sphinxext-opengraph >= 0.7.2, != 0.8.0
-furo >= 2022.9.29
+sphinx >= 6.2.1, < 7.0
+rstcheck >=6.1.2
+sphinxext-opengraph >= 0.8.1
+furo >= 2023.3.27
diff --git a/tox.ini b/tox.ini
index 17b9aca..59e59ea 100644
--- a/tox.ini
+++ b/tox.ini
@@ -83,7 +83,7 @@
 commands = {posargs}
 
 [testenv:doc]
-basepython = python3.7
+basepython = python3.8
 commands =
     sphinx-build -M html ./docs ./docs/_build -j auto
 deps =
@@ -91,7 +91,7 @@
     -rdocs/requirements.txt
 
 [testenv:rstcheck]
-basepython = python3.7
+basepython = python3.8
 commands =
     rstcheck --version
     rstcheck -r --report-level WARNING --ignore-roles api,phab .
@@ -100,7 +100,7 @@
     -rdocs/requirements.txt
 
 [testenv:sphinx]
-basepython = python3.7
+basepython = python3.8
 commands =
     sphinx-build -M html ./docs ./docs/_build -j auto -D html_theme=nature
 deps =

