[css-writing-modes-3] Tweak phrasing in implementation report

Author: frivoal

css-writing-modes-3/implementation-report-2019-08.html

@@ -96,6 +96,7 @@ <h3 id=summary><a href="#summary" class=self-link></a>1.1. Summary</h3>
 			each module is expected to have at least two independent implementations
 			of each of feature defined in the specification</q>.
 		With multiple browser engines (as well as non browsers) implementing the specification,
+		and each feature being implemented by two or more,
 		this criterion is fulfilled,
 		even though there remains a few tests for certain specificities of some features
 		that do not yet have two passing implementations.