Rework Graph Test for mocking missing imports

[JGSweets]

No description provided.

[taylorfturner]

Validated that this does fix the graph.py test issue mentioned in #733.

Running DATAPROFILER_SEED=0 python3 -m unittest discover -p "test*.py" returns the following

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ERROR: test_merge_profile_list (dataprofiler.tests.profilers.test_utils.TestProfileDistributedMerge)
A top-level function which takes in a list of profile objects, merges

======================================================================
ERROR: test_odd_merge_profile_list (dataprofiler.tests.profilers.test_utils.TestProfileDistributedMerge)
A top-level function which takes in a list of profile objects, merges
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OSError: [Errno 24] Too many open files

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Ran 905 tests in 818.749s

FAILED (errors=2)

• could be an issue with my local environment
• and totally can deal with this in a separate PR.... so this PR is still LGTM on my end 👍