set plots to run interactive mode (no blocking) (#214)

test/conftest.py

@@ -0,0 +1,12 @@
+"""Pytest configuration file."""
+
+import matplotlib.pyplot as plt
+
+def pytest_configure(config):
+    """Set configurations to be run before all testing."""
+
+    # Turn on interactive mode for matplotlib
+    #   In practice, this defaults `block=False` for plt.show()
+    #   This means that plots won't show and wait for input before proceeding
+    #   To run tests while showing plots, comment this out, or replace with `plt.ioff`
+    plt.ion()