Allow emulator tests to run also on a schedule

Also do 1 retry in case of failure

.gitlab-ci.yml

@@ -46,9 +46,17 @@ android test:
       - screenshots
     expire_in: 3 days
     when: on_failure
+  rules:
+    - if: '$CI_PIPELINE_SOURCE == "schedule"'
+    - if: '$CI_PIPELINE_SOURCE == "merge_request_event"'
+      changes:
+        - briar-android/**/*
       when: manual
-  except:
-    - tags
+      allow_failure: true
+  retry:
+    max: 1
+    when:
+      - script_failure
   tags:
     - kvm