Doc: section title should reflect the correct rule name

The instructions are about adding a `git_repository` rule, not an `new_http_archive` rule, as it was written in the section title.

Closes #2327.

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Reviewed-on: https://github.com/bazelbuild/bazel/pull/2327
PiperOrigin-RevId: 143451503
MOS_MIGRATED_REVID=143451503
diff --git a/site/versions/master/docs/tutorial/backend-server.md b/site/versions/master/docs/tutorial/backend-server.md
index a3dc8ff..45c6463 100644
--- a/site/versions/master/docs/tutorial/backend-server.md
+++ b/site/versions/master/docs/tutorial/backend-server.md
@@ -56,7 +56,7 @@
 the Java Servlet SDK and other libraries needed to build the App Engine
 applications.
 
-### Add a new\_http\_archive rule
+### Add a git\_repository rule
 
 When you built the Android app, you added a reference to the location on your
 filesystem where you downloaded and installed the Android SDK. For the