DOCSP-35195: fix duration values (#866)

Author: Chris Cho

source/fundamentals/monitoring/command-monitoring.txt

@@ -97,7 +97,7 @@ commandSucceeded
      commandName: "find",
      address: 'localhost:27017',
      connectionId: 812613,
-     duration: 1586380205,
+     duration: 15,
      reply: {
        cursor: {
          firstBatch: [
@@ -128,5 +128,5 @@ commandFailed
      address: 'localhost:27017',
      connectionId: 812613,
      failure: Error("something failed"),
-     duration: 1586380205
+     duration: 11
    }