Update Dask cluster tests

[thehomebrewnerd]

Updates test fixtures to prevent flaky Dask test behavior

Closes #2038

While this update seems to work on the surface, verifying this actually fixes the problem is a big challenging since the coverage tests don't fail consistently. If the changes in this PR do not fix the problem, we might try using the gen_cluster approach described in this issue: dask/distributed#4479

[codecov]

Codecov Report

Merging #2079 (2d26358) into main (8d09210) will increase coverage by 0.08%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main    #2079      +/-   ##
==========================================
+ Coverage   99.11%   99.20%   +0.08%     
==========================================
  Files         143      143              
  Lines       16554    16555       +1     
==========================================
+ Hits        16408    16423      +15     
+ Misses        146      132      -14     

Impacted Files	Coverage Δ
...utational_backend/test_calculate_feature_matrix.py	100.00% <100.00%> (+1.19%)	⬆️
featuretools/tests/conftest.py	100.00% <100.00%> (ø)
featuretools/tests/synthesis/test_dfs_method.py	100.00% <100.00%> (ø)
...computational_backends/calculate_feature_matrix.py	100.00% <0.00%> (+0.83%)	⬆️

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[rwedge]

Looks good