View source for Fluentbit syslog input tls

You can easily test the syslog using simple bash script.

You can create a test log with Ubuntu/Debian using gnutls-cli

Install
```
sudo apt-get install gnutls-bin
```

sendTLSLog.sh
```
ts=$(date "+%b %d %T")
echo "<142>$ts $HOSTNAME test: this is a test on test $RANDOM." | \
    gnutls-cli log.example.com --port=6514 --x509cafile=./root.ca.crt
```

Send log
```
bash sendTLSLog.sh
```

Here is a config snippet example below.

```
    [OUTPUT]
        Name      stdout
        Match     syslog.6514.tcp

    [INPUT]
        Name     syslog
        Parser   syslog-rfc3164
        Tag    syslog.6514.tcp
        Listen   0.0.0.0
        Port     6514
        Mode     tcp
        tls.verify no
        tls on
        tls.crt_file /app/certs/log.example.com.crt
        tls.key_file /app/certs/log.example.com.key
```

You may see some errors like
[2023/06/24 22:25:44] [error] [tls] error: unexpected EOF
But those are commonly tcp health probes from loadbalancer, liveness probes or other health checks. You can look at modifying or disabling these probes if you want.