Comment Out "environment" Section

When I pushed AppVeyor reported:

Error parsing appveyor.yml: "environment" section must be a mapping.
(Line: 7, Column: 13)

I assume this means they cannot be empty.  I had left only commented out
lines in it.

.appveyor.yml

@@ -4,7 +4,7 @@
 ##### General Configuiration #####
 version: '0.0.{build}'
 
-environment:
+#environment:
   # these variables are common to all jobs
 #  common_var1: value1
 #  common_var2: value2