Merge branch 'prometheus-metrics' into 'development'

Fixes bug where worker busy-ness would always be 100

See merge request eip/code-measures!41

worker/src/main/java/nl/tudelft/ewi/auta/worker/JobRunner.java

@@ -97,13 +97,13 @@ public class JobRunner {
         logger.debug("Worker running job {}", msg.getId());
 
         try (var job = this.splitter.split(msg)) {
-            gauge.set(0.0);
+            gauge.set(100.0);
             var message = this.checker.run(job);
             this.currentJob.set(null);
             replySender.send(message);
-            gauge.set(100.0);
+            gauge.set(0.0);
         } catch (final Exception ex) {
-            gauge.set(100.0);
+            gauge.set(0.0);
             logger.error("Exception while checking job {}", msg.getId(), ex);
             this.currentJob.set(null);
             try {

worker/src/main/java/nl/tudelft/ewi/auta/worker/Worker.java

@@ -107,7 +107,7 @@ public class Worker {
         final var busyGauge = Gauge.build()
                 .name("busy")
                 .help("Current busy status.").register();
-        busyGauge.set(100.0);
+        busyGauge.set(0.0);
         this.resolver.add(Gauge.class, busyGauge);
 
         final var checker = this.resolver.get(Checker.class);