Fix: add missing curl to dockerfile langflow-ai/langflow-helm-charts#40

[yashrajdighe]

Summary

This PR adds the missing curl package to the Dockerfiles and removes an empty continuation line as a lint fix.

Why is this needed?

The official Helm chart for langflow-runtime relies on curl for downloading flows, as defined in the startup args here.

Without curl, deployments fail with the following error:

Downloading flows from https://raw.githubusercontent.com/langflow-ai/langflow/dev/tests/data/basic_example.json to /app/flows/f9d3f53d.json
/bin/bash: line 1: curl: command not found

More context can be found in langflow-ai/langflow-helm-charts#40

Testing

The Docker build was tested locally, and the image builds successfully without errors. The flow download works as expected during runtime.