docs: sphinx 1.8.0 was released, so use it

diff --git a/docs/requirements.txt b/docs/requirements.txt
index 038b4d3..7a99a02 100644 (file)
--- a/docs/requirements.txt
+++ b/docs/requirements.txt
@@ -1,5 +1,5 @@
 breathe
 exhale
 breathe
 exhale

-sphinx>=1.8.0b1
+sphinx>=1.8.0

 sphinx_rtd_theme
 
 sphinx_rtd_theme