updater_sample: add http header demo

Added demo passing http headers to UpdateEngine#applyPayload.

Bug: 79483768
Test: manually
Change-Id: I3e9c812dba2066acadbcea8d07c933368806e20c
Signed-off-by: Zhomart Mukhamejanov <zhomart@google.com>
diff --git a/updater_sample/res/raw/sample.json b/updater_sample/res/raw/sample.json
index b6f4cdc..7ac8ffa 100644
--- a/updater_sample/res/raw/sample.json
+++ b/updater_sample/res/raw/sample.json
@@ -8,6 +8,7 @@
     "ab_streaming_metadata": {
         "__": "streaming_metadata is required only for streaming update",
         "__property_files": "name, offset and size of files",
+        "__authorization": "it will be sent to OTA package server as value of HTTP header - Authorization",
         "property_files": [
             {
                 "__filename": "name of the file in package",
@@ -17,6 +18,7 @@
                 "offset": 531,
                 "size": 5012323
             }
-        ]
+        ],
+        "authorization": "Basic my-secret-token"
     }
 }