OperatingSystemMXBeanProvider: Log exception for ReflectiveOperationException

Having the stacktrace when debugging this seems to be useful.

Change-Id: Ifa298ffb74eabdf0c6522c9831c533dd2ebd02eb
Signed-off-by: Edwin Kempin <ekempin@google.com>
diff --git a/java/com/google/gerrit/metrics/proc/OperatingSystemMXBeanProvider.java b/java/com/google/gerrit/metrics/proc/OperatingSystemMXBeanProvider.java
index 7256e8c..bc2846a 100644
--- a/java/com/google/gerrit/metrics/proc/OperatingSystemMXBeanProvider.java
+++ b/java/com/google/gerrit/metrics/proc/OperatingSystemMXBeanProvider.java
@@ -41,7 +41,7 @@
             return new OperatingSystemMXBeanProvider(sys);
           }
         } catch (ReflectiveOperationException e) {
-          log.debug(String.format("No implementation for %s: %s", name, e.getMessage()));
+          log.debug("No implementation for {}", name, e);
         }
       }
       log.warn("No implementation of UnixOperatingSystemMXBean found");