fix: Allow upload limit increase in kubernetes deployment

[Dexter192]

For kubernetes deployments, the maximum filesize for e.g. File Components is capped at 1MB due to the Nginx default limit

Since the Nginx service is started via a start-nginx.sh file, adding annotations to the ingress part of the values.yaml does not work
e.g.

ingress:
  enabled: true
  annotations:
    nginx.ingress.kubernetes.io/client-max-body-size: "200M"

or

frontend:
  nginx:
    client_max_body_size: "200M" 

The workaround described in the helm repo also does not work (for me) since the ingress.yaml template sets the service name and port for every path identically:

service:
  name: {{ $fullName }}
    port: 
      number: {{ $svcPort }}

The proposed change would allow the configuration of the client_max_body_size for the nginx configuration while using the existing environment variable LANGFLOW_MAX_FILE_SIZE_UPLOAD. Reusing this variable makes sense as it's purpose is to configure the maximum upload size.