Fix typo in tempest configuration page
Removes an extra 'what' from the string.
Change-Id: I5c84ea627c84721ed333514ec5c3a62358ab7585
Closes-Bug: #1485843
diff --git a/doc/source/configuration.rst b/doc/source/configuration.rst
index 3e6013d..aaaddf8 100644
--- a/doc/source/configuration.rst
+++ b/doc/source/configuration.rst
@@ -187,7 +187,7 @@
#. image_ref_alt
Both options are expecting an image id (not name) from nova. The *image_ref*
-option is what what will be used for booting the majority of servers in tempest.
+option is what will be used for booting the majority of servers in tempest.
*image_ref_alt* is used for tests that require 2 images such as rebuild. If 2
images are not available you can set both options to the same image_ref and
those tests will be skipped.