[Deployment] Setup fly.io deployment method and update docs (#1028)

Co-authored-by: sidmohanty11 <sidmohanty11@gmail.com>

embedchain/deployment/fly.io/Dockerfile

@@ -0,0 +1,13 @@
+FROM python:3.11-slim
+
+WORKDIR /app
+
+COPY requirements.txt /app/
+
+RUN pip install -r requirements.txt
+
+COPY . /app
+
+EXPOSE 8080
+
+CMD ["uvicorn", "app:app", "--host", "0.0.0.0", "--port", "8080"]