tests.hs -> runtests.hs.

src/chapter_1.md

@@ -31,7 +31,7 @@ defines a test suite named `test`, which in Tasty is of type
 `TestTree`. We will see below how to define these.
 
 To run the tests for an entire project, we write *test runner*, which
-we will normally call `tests.hs`. This test runner will import the
+we will normally call `runtests.hs`. This test runner will import the
 various `TestTrees`, combine them if necessary, and pass them to the
 `defaultMain` function provided by Tasty. When the program is run,
 Tasty will run the test suite and report any errors. If the test