DOC Fix davies_bouldin_score for numpydoc
diff --git a/maint_tools/test_docstrings.py b/maint_tools/test_docstrings.py
index d7cebff7344b9..6abed61972aad 100644
--- a/maint_tools/test_docstrings.py
+++ b/maint_tools/test_docstrings.py
@@ -120,7 +120,6 @@
     "sklearn.metrics.cluster._supervised.pair_confusion_matrix",
     "sklearn.metrics.cluster._supervised.rand_score",
     "sklearn.metrics.cluster._supervised.v_measure_score",
-    "sklearn.metrics.cluster._unsupervised.davies_bouldin_score",
     "sklearn.metrics.cluster._unsupervised.silhouette_samples",
     "sklearn.metrics.cluster._unsupervised.silhouette_score",
     "sklearn.metrics.pairwise.additive_chi2_kernel",
diff --git a/sklearn/metrics/cluster/_unsupervised.py b/sklearn/metrics/cluster/_unsupervised.py
index fd4933c1df17a..e353511d614f3 100644
--- a/sklearn/metrics/cluster/_unsupervised.py
+++ b/sklearn/metrics/cluster/_unsupervised.py
@@ -303,7 +303,7 @@ def calinski_harabasz_score(X, labels):
 
 
 def davies_bouldin_score(X, labels):
-    """Computes the Davies-Bouldin score.
+    """Compute the Davies-Bouldin score.
 
     The score is defined as the average similarity measure of each cluster with
     its most similar cluster, where similarity is the ratio of within-cluster

…_score passes numpydoc validation #21350


#### Reference Issues/PRs
DOC Ensures that sklearn.metrics.cluster._unsupervised.davies_bouldin_score #21350 


#### What does this implement/fix? Explain your changes.
Make summary start with infinitive verb. 

#### Any other comments?


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