Bug 1429603: Only run build and check as part of mingw32 build; r=jlund

Differential Revision: https://phabricator.services.mozilla.com/D414

--HG--
extra : rebase_source : e071e09acaaf500eb27a516cfd335703455255eb

taskcluster/ci/build/windows.yml

@@ -655,6 +655,7 @@ win32-mingw32/debug:
         max-run-time: 7200
     run:
         using: mozharness
+        actions: [build, check-test]
         script: mozharness/scripts/fx_desktop_build.py
         config:
             - builds/releng_base_firefox.py

testing/mozharness/configs/builds/releng_base_windows_32_mingw_builds.py

@@ -8,14 +8,6 @@ config = {
     # code block and also make sure this is synced with
     # releng_base_linux_64_builds.py
 
-    # note: overridden by MOZHARNESS_ACTIONS in TaskCluster tasks
-    'default_actions': [
-        'clobber',
-        'checkout-sources',
-        'build',
-        'upload-files',
-        'update',  # decided by query_is_nightly()
-    ],
     "buildbot_json_path": "buildprops.json",
     'app_ini_path': '%(obj_dir)s/dist/bin/application.ini',
     # decides whether we want to use moz_sign_cmd in env