Bug 1617074 - fix nightly beetmover bustage from normandy capabilities artifact, r=rail

Differential Revision: https://phabricator.services.mozilla.com/D63590

--HG--
extra : moz-landing-system : lando

taskcluster/taskgraph/manifests/firefox_candidates.yml

@@ -200,6 +200,9 @@ mapping:
     target.normandy.json:
         <<: *default
         description: "Metadata about the Normandy client of this build"
+        only_for_platforms:
+            - linux64-shippable
+            - win64-shippable
         pretty_name: firefox-${version}.normandy.json
         checksums_path: ${path_platform}/${locale}/target.normandy.json
     target_info.txt:

taskcluster/taskgraph/manifests/firefox_nightly.yml

@@ -196,6 +196,9 @@ mapping:
     target.normandy.json:
         <<: *default
         description: "Metadata about the Normandy client of this build"
+        only_for_platforms:
+            - linux64-shippable
+            - win64-shippable
         pretty_name: firefox-${version}.normandy.json
         checksums_path: firefox-${version}.normandy.json
     target_info.txt: