Issue-256: Updated the checkHeader to allow header_url in both video and image a… (#257)

* updated the checkHeader to allow header_url in both video and image as it is supported

* added document format

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Co-authored-by: denizkilic <[email protected]>

Author: Daniel AM

api/src/main/java/com/messagebird/objects/integrations/HSMComponent.java

@@ -166,10 +166,9 @@ private void checkHeaderText() throws IllegalArgumentException {
    * @throws IllegalArgumentException Occurs when type is not {@code HEADER} and format is not {@code IMAGE}.
    */
   private void checkHeaderUrl() throws IllegalArgumentException {
-    if (!(type.equals(HSMComponentType.HEADER)
-        && format.equals(HSMComponentFormat.IMAGE))
-    ) {
-      throw new IllegalArgumentException("\"header_url\" is available for only HEADER type and IMAGE format.");
+    if (!(type.equals(HSMComponentType.HEADER) &&
+            (format.equals(HSMComponentFormat.IMAGE)  || format.equals(HSMComponentFormat.VIDEO) || format.equals(HSMComponentFormat.DOCUMENT)))) {
+      throw new IllegalArgumentException("\"header_url\" is available for only HEADER type and IMAGE, VIDEO and DOCUMENT format.");
     }
   }
 }