`root_add_dict` should fail if the dict does not match exactly

[ewu63]

Description

Say you have a dictionary in the reference file, and use root_add_dict for training/testing. If the reference dictionary is a superset of the dictionary generated from testing, then the test is considered to pass, since we just loop over the generated dictionary keys, rather than the reference dictionary keys.

Steps to reproduce issue

Imagine if the reference JSON file contained the following dictionary

{'a':1, 'b':2, 'c':3}

and the dictionary generated by the test is

{'a':1, 'b':2}

Current behavior

root_add_dict will consider the test to be successful.

Expected behavior

The test should fail.