update metrics naming standars

Author: lizk886

src/main/java/com/uid2/admin/Main.java

@@ -440,7 +440,7 @@ private static void setupMetrics(MicrometerMetricsOptions metricOptions) {
         // retrieve image version (will unify when uid2-common is used)
         String version = Optional.ofNullable(System.getenv("IMAGE_VERSION")).orElse("unknown");
         Gauge appStatus = Gauge
-                .builder("app.status", () -> 1)
+                .builder("app_status", () -> 1)
                 .description("application version and status")
                 .tags("version", version)
                 .register(Metrics.globalRegistry);

src/main/java/com/uid2/admin/job/JobDispatcher.java

@@ -39,7 +39,7 @@ public JobDispatcher(
         this.maxRetries = maxRetries;
         this.clock = clock;
 
-        Gauge.builder("uid2.job_dispatcher.execution_duration_ms", this::getExecutionDuration)
+        Gauge.builder("uid2_job_dispatcher_execution_duration_ms", this::getExecutionDuration)
                 .tag("job_dispatcher", id)
                 .description("gauge for " + id + " execution time")
                 .register(Metrics.globalRegistry);