Fix a bug in CI workflow.

Author: ChenPi11

.github/workflows/build.yml

@@ -68,7 +68,7 @@ jobs:
       uses: actions/setup-python@v4
       with:
         python-version: 3.11.4
-    - run: pip install -r requirements.txt
+    - run: pip install Pillow
 
     - name: Get source distribution tarball
       run: |