added comments in test yml file

tests/config/test_config.py

@@ -3,6 +3,7 @@ import os
 
 test_cfg = """name: rw_test
 test: this is just a test.
+# this is a comment in the file
 one:
 - pink: martini
   red: apples
@@ -15,6 +16,7 @@ two:
 
 test_cfg2 = """name: rw_test
 test: this is just a test.
+# this is a comment in the file
 one:
 - pink: martini
   red: strawberry