Support duration events in `benchmark.mojo`.

mojo/tools/data/benchmarks

 # This file contains a list of Mojo benchmarks. For description of the file
 # format, see `mojo_benchmark --help`.
 
 benchmarks = [
   {
+    'name': 'Dart Traced App',
+    'app': 'https://core.mojoapps.io/dart_traced_application.mojo',
+    'duration': 10,
+    'measurements': [
+      'time_until/traced_application/function1',
+      'avg_duration/traced_application/function1',
+    ]
+  },
+  {
     'name': 'Trace me',
     'app': 'https://core.mojoapps.io/trace_me.mojo',
     'duration': 10,
     'measurements': [
       'time_until/trace_me/DoWork',
       'avg_duration/trace_me/DoWork',
     ]
   },
   {
     'name': 'Spinning cube',
     'app': 'https://core.mojoapps.io/spinning_cube.mojo',
     'duration': 10,
     'measurements': [
       'time_until/gpu/GpuScheduler:PutChanged',
     ]
   },
 ]