Delete unused import

Author: sbrannen

spring-tx/src/main/java/org/springframework/transaction/support/SimpleTransactionScope.java

@@ -23,7 +23,6 @@
 import org.springframework.beans.factory.ObjectFactory;
 import org.springframework.beans.factory.config.Scope;
 import org.springframework.lang.Nullable;
-import org.springframework.util.Assert;
 
 /**
  * A simple transaction-backed {@link Scope} implementation, delegating to