Deprecate PdfRichMediaAnnotation class

DEVSIX-3400

Autoported commit.
Original commit hash: [518b1b5b7]

Author: EvgenyB1001

itext/itext.kernel/itext/kernel/pdf/annot/PdfRichMediaAnnotation.cs

@@ -41,10 +41,13 @@ source product.
 For more information, please contact iText Software Corp. at this
 address: [email protected]
 */
+using System;
 using iText.Kernel.Geom;
 using iText.Kernel.Pdf;
 
 namespace iText.Kernel.Pdf.Annot {
+    [System.ObsoleteAttribute(@"Remove this class in 7.2. The deprecation relates to the fact that the prototype hasn't been implemented in a full yet and we do not expect the situation to change."
+        )]
     public class PdfRichMediaAnnotation : PdfAnnotation {
         public PdfRichMediaAnnotation(Rectangle rect)
             : base(rect) {

port-hash

@@ -1 +1 @@
-e8707cb5d57003270052389ae6f01203f757e881 
+518b1b5b70d16447e3f2290257efc3de8f50bc89