kunit: Documentation: Fixed non-ASCII character

This removes a non-ASCII character that was accidentally introduced.

Change-Id: I1eb992a42309abe89de7041cbabcc71c1e8ece72
Signed-off-by: Brendan Higgins <brendanhiggins@google.com>
diff --git a/Documentation/test/index.rst b/Documentation/test/index.rst
index e7c0a7e..8bb61cd 100644
--- a/Documentation/test/index.rst
+++ b/Documentation/test/index.rst
@@ -16,7 +16,7 @@
 ==============
 
 KUnit is a lightweight unit testing and mocking framework for the Linux kernel.
-These tests are able to be run locally on a developer’s workstation without a VM
+These tests are able to be run locally on a developer's workstation without a VM
 or special hardware.
 
 KUnit is heavily inspired by JUnit, Python's ``unittest.mock``, and