Bump sphinx from 2.4.0 to 2.4.1 (#464)

dependabot-preview[bot] · web-flow · commit b24cb357be7f · 2020-02-12T06:50:16.000Z
diff --git a/requirements/doc.txt b/requirements/doc.txt
@@ -1,3 +1,3 @@
-sphinx==2.4.0
+sphinx==2.4.1
 pyenchant==2.0.0
 sphinxcontrib-spelling==4.3.0
