plugin metrics: fix a typo about emit_count

When implementing metrics plugin mechanism, it should be
named emit_count instead of emit_records.

Closes: #3628

See
4a0335a

Signed-off-by: Kentaro Hayashi <hayashi@clear-code.com>

lib/fluent/plugin/bare_output.rb

@@ -70,7 +70,7 @@ def configure(conf)
         super
 
         @num_errors_metrics = metrics_create(namespace: "fluentd", subsystem: "bare_output", name: "num_errors", help_text: "Number of count num errors")
-        @emit_count_metrics = metrics_create(namespace: "fluentd", subsystem: "bare_output", name: "emit_records", help_text: "Number of count emits")
+        @emit_count_metrics = metrics_create(namespace: "fluentd", subsystem: "bare_output", name: "emit_count", help_text: "Number of count emits")
         @emit_records_metrics = metrics_create(namespace: "fluentd", subsystem: "bare_output", name: "emit_records", help_text: "Number of emit records")
         @emit_size_metrics =  metrics_create(namespace: "fluentd", subsystem: "bare_output", name: "emit_size", help_text: "Total size of emit events")
         @enable_size_metrics = !!system_config.enable_size_metrics