omemo: Ensure session_start is published

Signed-off-by: Maxime “pep” Buquet <pep@bouah.net>

plugins/omemo_plugin.py

@@ -53,6 +53,7 @@ class Plugin(E2EEPlugin):
         except (PluginCouldNotLoad,):
             log.exception('And error occured when loading the omemo plugin.')
 
+        self.core.xmpp['xep_0384'].session_start(self.core.xmpp.boundjid)
 
     def display_error(self, txt) -> None:
         self.api.information(txt, 'Error')