fixed typo in CoU

efficiency_module/static/efficiency_COU.html

@@ -52,9 +52,9 @@ appropriate if sufficient agitation is not applied and a boundary layer
 develops that slows the release rate or if the extraction is conducted
 under flow conditions.</li>
 <li>Possible chemical reactions are not considered. Therefore, if the
-polymer matrix undergoes substantive degradation during during the
-extraction test, the predictions may not be relevant. Further, the model
-does not consider the potential for individual extractable compounds to
+polymer matrix undergoes substantive degradation during the extraction
+test, the predictions may not be relevant. Further, the model does not
+consider the potential for individual extractable compounds to
 degrade.</li>
 <li>The test article is comprised of a single polymer matrix. In
 practice, complex devices may be comprised of multiple components and/or