Update sphinx requirement from <6.3,>=3.0 to >=3.0,<7.1 (#816)

dependabot[bot] · web-flow · commit 2b93645fc2f5 · 2023-05-02T09:24:04.000+02:00
diff --git a/docs/sphinx-requirements.txt b/docs/sphinx-requirements.txt
@@ -1,5 +1,5 @@
 # Sphinx builds the documentation
-sphinx>=3.0,<6.3
+sphinx>=3.0,<7.1
 
 # Sphinx dependencies
 Pygments>=2.6.1
