Rename dockerfile to Dockerfile

dockerfile → Dockerfile

@@ -41,7 +41,9 @@ USER appuser
 
 # Copy requirements file and install dependencies as the non-root user
 COPY --chown=appuser:appuser requirements.txt .
-RUN pip install --no-cache-dir -r requirements.txt
+RUN pip install --no-cache-dir \
+    -r requirements.txt \
+    --extra-index-url https://download.pytorch.org/whl/cpu
 
 # Clone the NeuTTS Air repository
 RUN git clone https://github.com/neuphonic/neutts-air.git