Wrote unit test for RequestTextFromFile -- word-generator.

TestCentre/UnitTests.fs

@@ -178,8 +178,15 @@
                 |> Async.RunSynchronously
                 |> countSentences
             Assert.Equal(desiredSentencesCount, result)
-        // YOU ARE HERE...
-        // - ADD TESTS FOR "CLEANING" FUNCTIONS
+
+        [<Fact>]
+        let ``RequestCleanTextFromFile returns intended number of sentences when using word-generator`` () =
+            let desiredSentencesCount = (ValidSentencesInput())
+            let result =
+                Pancake.RequestCleanTextFromFileAsync (ValidGibberishLevelInput()) desiredSentencesCount WordGenerator
+                |> Async.RunSynchronously
+                |> countSentences
+            Assert.Equal(desiredSentencesCount, result)
 
         [<Fact>]
         let ``RequestRandomText returns a string which contains a full stop`` () =