docs: update readme about pytest plugin

Author: deepankarm

README.md

@@ -700,15 +700,6 @@ markers = [
 markers = no_leaks: detect asyncio task leaks, thread leaks, and event loop blocking
 ```
 
-### Usage
-
-```python
-@pytest.mark.no_leaks
-@pytest.mark.asyncio
-async def test_no_task_leaks():
-    asyncio.create_task(asyncio.sleep(10))
-```
-
 You can also add it to the `conftest.py` file.
 
 ```python
@@ -722,6 +713,15 @@ def pytest_configure(config):
     )
 ```
 
+### Usage
+
+```python
+@pytest.mark.no_leaks
+@pytest.mark.asyncio
+async def test_no_task_leaks():
+    asyncio.create_task(asyncio.sleep(10))
+```
+
 ### Selective detection
 
 By default, all detectors are enabled. You can selectively enable or disable detectors using the `no_leaks` marker. For example, to only detect task leaks and event loop blocking, you can use the following: