Fix typo.
diff --git a/Doc/library/unittest.rst b/Doc/library/unittest.rst
index 5df6155..42ae8e2 100644
--- a/Doc/library/unittest.rst
+++ b/Doc/library/unittest.rst
@@ -194,7 +194,7 @@
 
 .. _unittest-command-line-interface:
 
-Command Line Interface
+Command-Line Interface
 ----------------------
 
 The unittest module can be used from the command line to run tests from