fixup display runner

Author: ianfixes

lib/arduino_ci/display_manager.rb

@@ -122,7 +122,7 @@ def run(env, args, **kwargs)
       with_display do |env_vars|
         env_vars = {} if env_vars.nil?
         env_vars.merge!(env) unless env.nil?
-        full_cmd = [env_vars] + args
+        full_cmd = env_vars.empty? ? args : [env_vars] + args
         puts "Running #{env_vars} $ #{args.join(' ')}"
         ret = system(*full_cmd, **kwargs)
       end