Bug 1887656 - Add macosx64-rust/opt to allowed mac-signing build platforms. r=rjl

The macOS Rust builds were falling back to the v1 macOS hardened signing configs (for
Firefox). Those were removed in bug 1886051 causing these signing jobs to fail.
Just needed to add the build platform to only-for-build-platforms so the transform picks
it up.

Differential Revision: https://phabricator.services.mozilla.com/D205577

--HG--
extra : amend_source : 62fe74963cf78544e4f5c201967e235c946c954d

taskcluster/ci/build-mac-signing/kind.yml

@@ -22,12 +22,11 @@ only-for-attributes:
 only-for-build-platforms:
     - macosx64-shippable/opt
     - macosx64/opt
+    - macosx64-rust/opt
     - macosx64/debug
 
 jobs:
     build-mac-signing:
         from-deps:
             group-by: single-with-filters
-        treeherder:
-            symbol: BMS
         enable-signing-routes: false

taskcluster/ci/build-signing/kind.yml

@@ -23,6 +23,7 @@ only-for-attributes:
 not-for-build-platforms:
     - macosx64-shippable/opt
     - macosx64/opt
+    - macosx64-rust/opt
     - macosx64/debug
 
 jobs:

taskcluster/comm_taskgraph/transforms/hardened_signing.py

@@ -39,7 +39,7 @@ def add_hardened_sign_config(config, jobs):
             "hardened-sign-config",
             {"hardened-signing-type": hardened_signing_type},
         )
-        if type(evaluated) != list:
+        if not isinstance(evaluated, list):
             raise Exception("hardened-sign-config must be a list")
 
         for sign_cfg in evaluated: