Delete unused targets in Vertex annotation

Author: Jegors Čemisovs

sample-cli/src/main/java/lv/id/jc/graph/cli/Vertex.java

@@ -6,9 +6,9 @@
 import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
 
-import static java.lang.annotation.ElementType.*;
+import static java.lang.annotation.ElementType.PARAMETER;
 
-@Target({METHOD, FIELD, ANNOTATION_TYPE, CONSTRUCTOR, PARAMETER})
+@Target({PARAMETER})
 @Retention(RetentionPolicy.RUNTIME)
 @Constraint(validatedBy = {Commands.class})
 public @interface Vertex {