migrate to dhtnet namespace

Change-Id: I7143a010bd83e8cfa7a3c8c3072ed23f6f0ba8e3
diff --git a/src/security/tls_session.cpp b/src/security/tls_session.cpp
index e84d277..94078a3 100644
--- a/src/security/tls_session.cpp
+++ b/src/security/tls_session.cpp
@@ -47,7 +47,7 @@
 #include <cstdlib>
 #include <unistd.h>
 
-namespace jami {
+namespace dhtnet {
 namespace tls {
 
 static constexpr const char* DTLS_CERT_PRIORITY_STRING {