Improve the structure of CI (#911)

test/README.md

@@ -0,0 +1,26 @@
+# Run Unit Tests
+
+## Test Frontend Language
+```
+cd sglang/test/lang
+export OPENAI_API_KEY=sk-*****
+
+# Run a single file
+python3 test_openai_backend.py
+
+# Run a suite
+python3 run_suite.py --suite minimal
+```
+
+## Test Backend Runtime
+```
+cd sglang/test/srt
+
+# Run a single file
+python3 test_eval_accuracy.py
+
+# Run a suite
+python3 run_suite.py --suite minimal
+```
+
+