[ci.yaml] Add LUCI config information (#87583)

diff --git a/TESTOWNERS b/TESTOWNERS
index caa0ef7..555a144 100644
--- a/TESTOWNERS
+++ b/TESTOWNERS
@@ -221,3 +221,4 @@
 # fuchsia_precache @zanderso @flutter/tool
 # skp_generator @Hixie
 # test_ownership @keyonghan
+# verify_binaries_codesigned @christopherfujino @flutter/releases