remove errant paren

Author: trevorcampbell

source/clustering.md

@@ -775,7 +775,7 @@ total WSSD, since the cluster center (denoted by large shapes with black outline
 the other hand, if we set K greater than 3, the clustering subdivides subgroups of data; this does indeed still
 decrease the total WSSD, but by only a *diminishing amount*. If we plot the total WSSD versus the number of
 clusters, we see that the decrease in total WSSD levels off (or forms an "elbow shape") when we reach roughly
-the right number of clusters ({numref}`toy-kmeans-elbow`)).
+the right number of clusters ({numref}`toy-kmeans-elbow`).
 
 :::{glue:figure} toy-kmeans-elbow
 :figwidth: 700px