MythSingleDownload: Set a User-Agent

Refs #13488
Signed-off-by: Paul Harrison <pharrison@mythtv.org>
(cherry picked from commit 017440b)

mythtv/libs/libmythbase/mythsingledownload.cpp

@@ -1,5 +1,6 @@
 
 #include "mythsingledownload.h"
+#include "mythversion.h"
 #include "mythlogging.h"
 
 /*
@@ -20,6 +21,8 @@ bool MythSingleDownload::DownloadURL(const QUrl &url, QByteArray *buffer,
 
     // the HTTP request
     QNetworkRequest req(url);
+    req.setRawHeader("User-Agent",
+                     "MythTV v" MYTH_BINARY_VERSION " MythSingleDownload");
     m_replylock.lock();
     m_reply = m_mgr.get(req);
     m_replylock.unlock();