add random seed argument

Signed-off-by: Nathaniel <NathanielF@users.noreply.github.com>

Author: NathanielF

causalpy/tests/test_pymc_experiments.py

@@ -63,7 +63,13 @@ def test_regression_kink_gradient_change():
 
 def test_inverse_prop():
     df = cp.load_data("nhefs")
-    sample_kwargs = {"tune": 100, "draws": 500, "chains": 2, "cores": 2}
+    sample_kwargs = {
+        "tune": 100,
+        "draws": 500,
+        "chains": 2,
+        "cores": 2,
+        "random_seed": 100,
+    }
     result = cp.pymc_experiments.InversePropensityWeighting(
         df,
         formula="trt ~ 1 + age + race",