Doc nit: remove local=True from http_archive example

`http_archive` is not local - it does not re-download external repos on bazel server restart. Having `local=True` in the example is somewhat confusing.

Looks it was leftover after some older change:
https://github.com/bazelbuild/bazel/commit/13ecdf583301a94484a1ae0eb27c56fcf3248dc5#diff-1f760cde585b814b5608e64ade35cfa8f6fc0b1082316adc2f1bac412169a10eL41

Closes #22084.

PiperOrigin-RevId: 627954043
Change-Id: Ie25f5f0141401e194be99c9d02ec81c0ab619484
diff --git a/site/en/extending/repo.md b/site/en/extending/repo.md
index e38cea2..1b3e366 100644
--- a/site/en/extending/repo.md
+++ b/site/en/extending/repo.md
@@ -40,7 +40,6 @@
 ```python
 http_archive = repository_rule(
     implementation=_impl,
-    local=True,
     attrs={
         "url": attr.string(mandatory=True)
         "sha256": attr.string(mandatory=True)