Fix minor documentation build issue (#1139)

Signed-off-by: Abolfazl Shahbazi <[email protected]>

AudioQnA/benchmark/performance/README.md

@@ -51,11 +51,11 @@ LimitNOFILE=65536:1048576
 sudo systemctl daemon-reload; sudo systemctl restart containerd
 ```
 
-### Test Steps
+## Test Steps
 
 Please deploy AudioQnA service before benchmarking.
 
-##### Run Benchmark Test
+### Run Benchmark Test
 
 Before the benchmark, we can configure the number of test queries and test output directory by:
 
@@ -72,6 +72,6 @@ bash benchmark.sh -n <node_count>
 
 The argument `-n` refers to the number of test nodes.
 
-##### 4. Data collection
+### Data collection
 
 All the test results will come to this folder `/tmp/benchmark_output` configured by the environment variable `TEST_OUTPUT_DIR` in previous steps.