pdcp: properly stop metrics timer

Author: alvasMan

lib/pdcp/pdcp_entity_rx.cpp

@@ -82,6 +82,7 @@ void pdcp_entity_rx::stop()
     stopped = true;
     reordering_timer.stop();
     token_mngr.stop();
+    metrics_timer.stop();
     logger.log_debug("Stopped PDCP entity");
   }
 }

lib/pdcp/pdcp_entity_tx.cpp

@@ -86,6 +86,7 @@ void pdcp_entity_tx::stop()
     if (cfg.discard_timer.has_value()) {
       discard_timer.stop();
     }
+    metrics_timer.stop();
     logger.log_debug("Stopped PDCP entity");
   }
 }