app,sched: consistent naming for avg_prach_delay metric

Author: jonathan-srs

apps/units/flexible_o_du/o_du_high/du_high/metrics/consumers/scheduler_metrics_consumers.cpp

@@ -237,7 +237,7 @@ void scheduler_cell_metrics_consumer_log::handle_metric(const std::optional<sche
       fmt::format_to(std::back_inserter(buffer), " max_pusch_harq_delay={}ms", max_pusch_delay);
     }
     fmt::format_to(
-        std::back_inserter(buffer), " avg_prach_delay_slots={:.3}", format_value_or(cell.avg_prach_delay_slots, "n/a"));
+        std::back_inserter(buffer), " avg_prach_delay={:.3}", format_value_or(cell.avg_prach_delay_slots, "n/a"));
     if (not cell.events.empty()) {
       fmt::format_to(std::back_inserter(buffer), " events=[");
       bool first = true;