Remove extraneous comma from iOS app page in tutorial

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MOS_MIGRATED_REVID=104241690
diff --git a/site/docs/tutorial/ios-app.md b/site/docs/tutorial/ios-app.md
index a128457..8990817 100644
--- a/site/docs/tutorial/ios-app.md
+++ b/site/docs/tutorial/ios-app.md
@@ -36,7 +36,7 @@
 
 ## Add an objc_library rule
 
-Bazel provides several build rules, that you can use to build an app for the
+Bazel provides several build rules that you can use to build an app for the
 iOS platform. For this tutorial, you'll first use the
 [`objc_library`](/docs/build-encyclopedia.html#objc_library) rule to tell Bazel
 how to build an