Updates benchmark default output format for dashboard (#161)

# Description

Updates the benchmark scripts with new additional output format that can
be used for tracking results on a dashboard.

## Checklist

- [x] I have run the [`pre-commit` checks](https://pre-commit.com/) with
`./isaaclab.sh --format`
- [ ] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [ ] I have added tests that prove my fix is effective or that my
feature works
- [ ] I have updated the changelog and the corresponding version in the
extension's `config/extension.toml` file
- [ ] I have added my name to the `CONTRIBUTORS.md` or my name already
exists there

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source/standalone/benchmarks/benchmark_non_rl.py

@@ -28,9 +28,9 @@ parser.add_argument("--num_frames", type=int, default=100, help="Number of envir
 parser.add_argument(
     "--benchmark_backend",
     type=str,
-    default="OsmoKPIFile",
-    choices=["LocalLogMetrics", "JSONFileMetrics", "OsmoKPIFile"],
-    help="Benchmarking backend options, defaults OsmoKPIFile",
+    default="OmniPerfKPIFile",
+    choices=["LocalLogMetrics", "JSONFileMetrics", "OsmoKPIFile", "OmniPerfKPIFile"],
+    help="Benchmarking backend options, defaults OmniPerfKPIFile",
 )
 
 # append AppLauncher cli args

source/standalone/benchmarks/benchmark_rlgames.py

@@ -28,9 +28,9 @@ parser.add_argument("--max_iterations", type=int, default=10, help="RL Policy tr
 parser.add_argument(
     "--benchmark_backend",
     type=str,
-    default="OsmoKPIFile",
-    choices=["LocalLogMetrics", "JSONFileMetrics", "OsmoKPIFile"],
-    help="Benchmarking backend options, defaults OsmoKPIFile",
+    default="OmniPerfKPIFile",
+    choices=["LocalLogMetrics", "JSONFileMetrics", "OsmoKPIFile", "OmniPerfKPIFile"],
+    help="Benchmarking backend options, defaults OmniPerfKPIFile",
 )
 
 # append AppLauncher cli args

source/standalone/benchmarks/benchmark_rsl_rl.py

@@ -32,9 +32,9 @@ parser.add_argument("--max_iterations", type=int, default=10, help="RL Policy tr
 parser.add_argument(
     "--benchmark_backend",
     type=str,
-    default="OsmoKPIFile",
-    choices=["LocalLogMetrics", "JSONFileMetrics", "OsmoKPIFile"],
-    help="Benchmarking backend options, defaults OsmoKPIFile",
+    default="OmniPerfKPIFile",
+    choices=["LocalLogMetrics", "JSONFileMetrics", "OsmoKPIFile", "OmniPerfKPIFile"],
+    help="Benchmarking backend options, defaults OmniPerfKPIFile",
 )
 
 # append RSL-RL cli arguments