Comment (by Zach Etienne):

@Roland Haas I just pushed a new revision. The midpoint method now demonstrates 2nd order convergence in the convergence test. I also updated the tests.cc file to properly use midpoints when midpoint integration is selected for the test_pi_symmetric_sphere_integral() function as well. All test results for tests that used the midpoint method were updated.

No other integration methods were affected, and I demonstrated this by confirming their test results remain unchanged.

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Ticket URL: https://bitbucket.org/einsteintoolkit/tickets/issues/2398/multipole-default-midpoint-integration