Test for logistic fit and minor fix to fit func

testing_project/test_logistic_fit.py

@@ -0,0 +1,11 @@
+from numpy.testing import assert_allclose
+
+from logistic import iterate_f
+from logistic_fit import fit_r
+
+def test_fit_r():
+    r = 3.421
+    trajectory = iterate_f(0.3, r, 23)
+    fit_result_r = fit_r(trajectory)
+    assert_allclose(r, fit_result_r)
+