Fix GN visibility for openscreen_cast_auth_util_fuzzer

This updates the visibility list for certificate_boringssl to allow all
targets within //components/media_router/common/providers/cast/channel
to depend on it.

This is necessary because a change to the fuzzer_test template in
Chromium for android causes intermediate generated targets to inherit
the fuzzer's dependencies. This breaks the strict target-name visibility
check

Bug: 506174854
Change-Id: I83702f3e353d9f76aedf3ede9387de987bca937b
Reviewed-on: https://chromium-review.googlesource.com/c/openscreen/+/7793868
Commit-Queue: Edgar Aguilar <eledgar@google.com>
Reviewed-by: Mark Foltz <mfoltz@chromium.org>
Reviewed-by: Titouan Rigoudy <titouan@chromium.org>

cast/common/BUILD.gn

diff --git a/cast/common/BUILD.gn b/cast/common/BUILD.gn
index d306745..cca52ce 100644
--- a/cast/common/BUILD.gn
+++ b/cast/common/BUILD.gn
@@ -56,7 +56,7 @@
     "../standalone_receiver:cast_receiver",
     "../standalone_sender:cast_sender",
     "../test:*",
-    "//components/media_router/common/providers/cast/channel:openscreen_cast_auth_util_fuzzer",
+    "//components/media_router/common/providers/cast/channel:*",
   ]
   public = []
   sources = [