Bump sphinx-autodoc-typehints from 1.21.7 to 1.21.8 (#41)

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Camille <78221213+clatapie@users.noreply.github.com>

Author: dependabot[bot]

pyproject.toml

@@ -55,7 +55,7 @@ doc = [
     "pytest-sphinx==0.5.0",
     "pyvista==0.37.0",
     "sphinx-autobuild==2021.3.14",
-    "sphinx-autodoc-typehints==1.21.7",
+    "sphinx-autodoc-typehints==1.21.8",
     "sphinx-copybutton==0.5.1",
     "sphinx-notfound-page==0.8.3",
     "sphinx-gallery==0.11.1",