Update dependency Sphinx to v4.0.1 (#644)

renovate[bot] · web-flow · commit 9d1ae4614472 · 2021-05-10T23:04:17.000+03:00
diff --git a/requirements-doc.txt b/requirements-doc.txt
@@ -1,2 +1,2 @@
-Sphinx==4.0.0
+Sphinx==4.0.1
 sphinx-rtd-theme==0.5.2
