remove unused import

Author: wassertim

src/main/java/io/github/wassertim/dynamodb/toolkit/generation/FieldConstantsGenerator.java

@@ -3,7 +3,6 @@
 import java.io.IOException;
 import java.io.PrintWriter;
 import java.time.Instant;
-import java.util.Set;
 
 import javax.annotation.processing.Filer;
 import javax.annotation.processing.Messager;