[Cython] Adjust solver parameters for TestFlowReactor.test_reacting

This avoids CVODES failures that otherwise occur on some machines.

interfaces/cython/cantera/test/test_reactor.py

@@ -473,6 +473,7 @@ class TestFlowReactor(utilities.CanteraTest):
         net.add_reactor(r)
         net.atol = 1e-18
         net.rtol = 1e-9
+        net.max_err_test_fails = 10
 
         t = 0
         self.assertNear(r.speed, 10 / r.density)