Merge pull request #13926 from pytest-dev/patchback/backports/9.0.x/d587e0cf84bd815f4545a5091ab26f992580ac37/pr-13919

[PR #13919/d587e0cf backport][9.0.x] doc: a rendering fix & update RTD to Python 3.13

Author: bluetech

.readthedocs.yaml

@@ -17,7 +17,7 @@ build:
   os: ubuntu-24.04
   tools:
     python: >-
-      3.12
+      3.13
   apt_packages:
     - inkscape
   jobs:

doc/en/explanation/goodpractices.rst

@@ -354,7 +354,7 @@ See the :confval:`strict` documentation for the options it enables and their eff
 If pytest adds new strictness options in the future, they will also be enabled in strict mode.
 Therefore, you should only enable strict mode if you use a pinned/locked version of pytest,
 or if you want to proactively adopt new strictness options as they are added.
-If you don't want to automatically pick up new options, you can enable options individually::
+If you don't want to automatically pick up new options, you can enable options individually:
 
 .. tab:: toml
 
@@ -376,7 +376,7 @@ If you don't want to automatically pick up new options, you can enable options i
         strict_parametrization_ids = true
         strict_xfail = true
 
-If you want to use strict mode but having trouble with a specific option, you can turn it off individually::
+If you want to use strict mode but having trouble with a specific option, you can turn it off individually:
 
 .. tab:: toml
 

tox.ini

@@ -111,7 +111,7 @@ setenv =
 description =
     build the documentation site under \
     `{toxinidir}{/}doc{/}en{/}_build{/}html` with `{basepython}`
-basepython = python3.12 # sync with rtd to get errors
+basepython = python3.13 # Sync with .readthedocs.yaml to get errors.
 usedevelop = True
 deps =
     -r{toxinidir}/doc/en/requirements.txt