fix ci; specify flash-attn version

Author: YeAnbang

.github/workflows/run_chatgpt_examples.yml

@@ -29,10 +29,6 @@ jobs:
       - name: Checkout ColossalAI
         uses: actions/checkout@v2
 
-      - name: Install flash-attention
-        run: |
-          pip install flash-attn==2.7.4.post1 --no-build-isolation
-
       - name: Install Colossal-AI
         run: |
           pip install --no-cache-dir -v -e .
@@ -47,6 +43,10 @@ jobs:
           pip install --no-cache-dir -v .
           pip install --no-cache-dir -r examples/requirements.txt
 
+      - name: Install flash-attention
+        run: |
+          pip install flash-attn==2.7.4.post1 --no-build-isolation
+
       - name: Install Transformers
         run: |
           pip install --no-cache-dir transformers==4.36.2