xmrig-proxy v6.11.0 linux-x64 | Inconsistent HTTP API results, "Connection reset by peer"
Hello,

I'm getting really inconsistent results from the HTTP API, most of the time it drops the connection but sometimes it works :
_Note : I've got a daemon which gets and logs every 10s the number of miners using the API. It also is affected by this issue._

Trying 10 times at an approximate 1s interval :
```
# curl localhost:8888 -v
* Rebuilt URL to: localhost:8888/
*   Trying ::1...
* TCP_NODELAY set
* connect to ::1 port 8888 failed: Connection refused
*   Trying 127.0.0.1...
* TCP_NODELAY set
* Connected to localhost (127.0.0.1) port 8888 (#0)
> GET / HTTP/1.1
> Host: localhost:8888
> User-Agent: curl/7.61.1
> Accept: */*
>
* Recv failure: Connection reset by peer
* Closing connection 0
curl: (56) Recv failure: Connection reset by peer
```
But suddenly:
```
# curl localhost:8888 -v
* Rebuilt URL to: localhost:8888/
*   Trying ::1...
* TCP_NODELAY set
* connect to ::1 port 8888 failed: Connection refused
*   Trying 127.0.0.1...
* TCP_NODELAY set
* Connected to localhost (127.0.0.1) port 8888 (#0)
> GET / HTTP/1.1
> Host: localhost:8888
> User-Agent: curl/7.61.1
> Accept: */*
>
< HTTP/1.1 401 Unauthorized
< Access-Control-Allow-Headers: Authorization, Content-Type
< Access-Control-Allow-Methods: GET, PUT, POST, DELETE
< Access-Control-Allow-Origin: *
< Connection: close
< Content-Length: 50
< Content-Type: application/json
<
{
    "status": 401,
    "error": "Unauthorized"
* Closing connection 0
```
**More details :**
Server OS:
```
#  cat /etc/os-release
NAME="CentOS Linux"
VERSION="8"
ID="centos"
ID_LIKE="rhel fedora"
VERSION_ID="8"
PLATFORM_ID="platform:el8"
PRETTY_NAME="CentOS Linux 8"
ANSI_COLOR="0;31"
CPE_NAME="cpe:/o:centos:centos:8"
HOME_URL="https://centos.org/"
BUG_REPORT_URL="https://bugs.centos.org/"
CENTOS_MANTISBT_PROJECT="CentOS-8"
CENTOS_MANTISBT_PROJECT_VERSION="8"
```

HTTP API config in config.json :

```
"api": {
        "id": null,
        "worker-id": "██████"
    },
    "http": {
        "enabled": true,
        "host": "127.0.0.1",
        "port": 8888,
        "access-token": "████████████████████████████████",
        "restricted": false
    },

```
Edit : the previous version is also affected 
