Fix default value to match array type of pillar

salt/files/master.d/engine.conf

@@ -1,7 +1,7 @@
 #
 # This file is managed by Salt! Do not edit by hand!
 #
-{%- set engines = salt['pillar.get']('salt:engines', {}) -%}
+{%- set engines = salt['pillar.get']('salt:engines', []) -%}
 {%- set engines = salt['pillar.get']('salt:master:engines', default=engines, merge=True) -%}
 {%- set engines_profiles = salt['pillar.get']('salt:engines_profiles', {}) -%}
 {%- set engines_profiles = salt['pillar.get']('salt:master:engines_profiles', default=engines_profiles, merge=True) -%}