fix the bug that weights are not initialized correctly in adaptive_parzen… (#5032)

* fix the bug that weights are not defined correctly in adaptive_parzen_normal of TPE

* Align code style
Co-authored-by: down-lee <down.lee@navercorp.com>
Co-authored-by: liuzhe-lz <40699903+liuzhe-lz@users.noreply.github.com>

nni/algorithms/hpo/tpe_tuner.py

@@ -411,7 +411,7 @@ def adaptive_parzen_normal(args, history_mus, prior_mu, prior_sigma):
     n = min(100, len(mus) + 1)
     sigmas = np.clip(sigmas, prior_sigma / n, prior_sigma)
 
-    weights = np.append(linear_forgetting_weights(args, len(mus)), args.prior_weight)
+    weights = np.append(linear_forgetting_weights(args, len(mus) - 1), args.prior_weight)
     weights = weights[order]
 
     return weights / np.sum(weights), mus, sigmas