chore(docs): Update writing-tests.md with note about code snippets comments (NativeScript#5489)

Alexander Vakrilov · web-flow · commit 45bf5b8f5760 · 2018-03-13T15:42:51.000+01:00
* Update WritingUnitTests.md

* chore: typo
diff --git a/WritingUnitTests.md b/WritingUnitTests.md
@@ -82,3 +82,7 @@ export function test_getJSON(done) {
         (error) => { done(error); }); // fail
 };
 ```
+
+# Misc
+
+When looking into the code of the existing tests, you might encounter strange comments looking like this `// >> animation-chaining`. These are markers for code snippets generated in the docs documetation. They are not related to testing so you don't need to add any of those in your tests.
