Pin Python in docs build (#528)

* Pin Python in docs build

* ?

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

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Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Author: martinRenou

docs/environment.yml

@@ -2,6 +2,7 @@ name: jupytercad
 channels:
   - conda-forge
 dependencies:
+  - python=3.12
   - pip
   - sphinx
   - pydata-sphinx-theme

docs/source/conf.py

@@ -25,4 +25,4 @@
 todo_include_todos = False
 htmlhelp_basename = "jupytercaddoc"
 
-intersphinx_mapping = {"https://docs.python.org": None}
+intersphinx_mapping = {"python": ("https://docs.python.org/3", None)}