build(deps): bump sphinx-gallery from 0.19.0 to 0.20.0 in /requirements (#2795)

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

Author: dependabot[bot]

requirements/requirements_docs.txt

@@ -10,7 +10,7 @@ pytest-sphinx==0.6.3
 pyvista==0.46.4
 sphinx==8.2.3
 sphinx-copybutton==0.5.2
-sphinx-gallery==0.19.0
+sphinx-gallery==0.20.0
 sphinx-jinja==2.0.2
 sphinx-notfound-page==1.1.0
 sphinx-reredirects==0.1.6