Enable http1.0 on Envoy Gateway by default

[theboringstuff]

Description

There are clients which are using http1.0, so to be better compatible with ingress-nginx, we need to enable http1.0 support in envoy gateway

Solution

• Enabled http1.0 support by default

Test Cases

1. Install KubeMarine cluster with Envoy Gateway
2. Check that HTTP 1.0 requests DO NOT return 426 status code, see example below (put your ENVOY_IP and ENVOY_HTTPS_PORT)

Before (note first requests return 426, while others return 404)

$ curl -s -o /dev/null -w "%{http_code}\n" -k https://$ENVOY_IP:$ENVOY_HTTPS_PORT --http1.0
426
$ curl -s -o /dev/null -w "%{http_code}\n" -k https://$ENVOY_IP:$ENVOY_HTTPS_PORT --http1.1
404
$ curl -s -o /dev/null -w "%{http_code}\n" -k https://$ENVOY_IP:$ENVOY_HTTPS_PORT --http2
404

After (note all requests now return 404)

$ curl -s -o /dev/null -w "%{http_code}\n" -k https://$ENVOY_IP:$ENVOY_HTTPS_PORT --http1.0
404
$ curl -s -o /dev/null -w "%{http_code}\n" -k https://$ENVOY_IP:$ENVOY_HTTPS_PORT --http1.1
404
$ curl -s -o /dev/null -w "%{http_code}\n" -k https://$ENVOY_IP:$ENVOY_HTTPS_PORT --http2
404

Checklist

• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• There is no breaking changes, or migration patch is provided
• Integration CI passed
• Unit tests. If Yes list of new/changed tests with brief description
• There is no merge conflicts