[tutorial] edited hands-on practices (#1899)

* Add handson to ColossalAI.

* Change names of handsons and edit sequence parallel example.

* Edit wrong folder name

* resolve conflict

* delete readme

examples/tutorial/opt/inference/benchmark/locustfile.py

@@ -0,0 +1,15 @@
+from locust import HttpUser, task
+from json import JSONDecodeError
+
+
+class GenerationUser(HttpUser):
+    @task
+    def generate(self):
+        prompt = 'Question: What is the longest river on the earth? Answer:'
+        for i in range(4, 9):
+            data = {'max_tokens': 2**i, 'prompt': prompt}
+            with self.client.post('/generation', json=data, catch_response=True) as response:
+                if response.status_code in (200, 406):
+                    response.success()
+                else:
+                    response.failure('Response wrong')