when a file was Uploaded using httpclient content-type was not right (#636)

Issue: 99759

Author: iroqueta

java/src/main/java/com/genexus/internet/HttpContext.java

@@ -1788,7 +1788,8 @@ public boolean isRestService()
 								{"svg"	, "image/svg+xml"},
 								{"tgz"	, "application/x-compressed"},
 								{"zip"	, "application/x-zip-compressed"},
-								{"gz"	, "application/x-gzip"}
+								{"gz"	, "application/x-gzip"},
+								{"json"	, "application/json"}
 								};
 
 		public boolean willRedirect()