[tracer] Suppress non-hermetic actions

Suppresses all non-hermetic actions used by the core.64 build
configurations in infra.

Tested by running:
`fx set core.x64 --with-base //bundles/buildbot:core --with
//bundles:build_infra --with //bundles:test_infra --variant asan-ubsan
--args build_should_trace_actions=true && fx build`

Bug: 64127
Change-Id: Ib1b7111f04231205a2c0e49d497edd396ee7bef9
Reviewed-on: https://fuchsia-review.googlesource.com/c/topaz/+/469497
Reviewed-by: David Turner <digit@google.com>
Reviewed-by: P.Y. Laligand <pylaligand@google.com>
Commit-Queue: Anirudh Mathukumilli <rudymathu@google.com>
diff --git a/tools/protobuf/protobuf_dart.gni b/tools/protobuf/protobuf_dart.gni
index fdb9c7d..949264f 100644
--- a/tools/protobuf/protobuf_dart.gni
+++ b/tools/protobuf/protobuf_dart.gni
@@ -80,6 +80,7 @@
   action(proto_gen_target) {
     visibility = [ ":*" ]
 
+    hermetic_deps = false
     script = "//third_party/protobuf/protoc_wrapper.py"
     sources = invoker.sources
     inputs = [ protoc_path ] + invoker.sources