Update ios-app.md to load git_repository

Closes #9302.

PiperOrigin-RevId: 266965298

site/docs/tutorial/ios-app.md

diff --git a/site/docs/tutorial/ios-app.md b/site/docs/tutorial/ios-app.md
index fa5c7e4..71b6503 100644
--- a/site/docs/tutorial/ios-app.md
+++ b/site/docs/tutorial/ios-app.md
@@ -100,6 +100,7 @@
 rules to your `WORKSPACE` file:
 
 ```
+load("@bazel_tools//tools/build_defs/repo:git.bzl", "git_repository")
 git_repository(
     name = "build_bazel_rules_apple",
     remote = "https://github.com/bazelbuild/rules_apple.git",