Fix invalid port name with uppercase characters

[denverdino]

When there are multiple protocol for one port, the generated port name is invalid which has uppercase chars

E.g.

version: '2'
services:
  bootstrap:
    image: test
    ports:
      - "1234:1234"
      - "1234:1234/udp"

The generated service config is as following

apiVersion: v1
kind: Service
metadata:
  annotations:
    kompose.version: 1.13.0 (84fa826)
  creationTimestamp: null
  labels:
    io.kompose.service: bootstrap
  name: bootstrap
spec:
  ports:
  - name: "1234"
    port: 1234
    targetPort: 1234
  - name: 1234-UDP
    port: 1234
    protocol: UDP
    targetPort: 1234
  selector:
    io.kompose.service: bootstrap

The following exception will be return when creating service

The Service "bootstrap" is invalid: spec.ports[1].name: Invalid value: "1234-UDP": a DNS-1123 label must consist of lower case alphanumeric characters or '-', and must start and end with an alphanumeric character (e.g. 'my-name', or '123-abc', regex used for validation is 'a-z0-9?')

We should append the lower case of protocol as part of the port name.

Thanks

[hangyan]

@denverdino Thanks!