[PROTOCOL_ERROR] Strict KEX mode encountered a message that is not permitted at this time

Hi Team,

we get the exception at the bottom in connection to sftp client authentication:

```
client = new SSHClient();
client.loadKnownHosts();
client.addHostKeyVerifier(new PromiscuousVerifier());
client.setConnectTimeout(12000);
client.getConnection().getKeepAlive().setKeepAliveInterval(12000);
client.connect(host, port);
client.authPassword(uname, password);
```

```java
net.schmizz.sshj.transport.TransportException:
[PROTOCOL_ERROR] Strict KEX mode encountered a message that is not permitted at this time
net.schmizz.sshj.transport.TransportImpl.gotDisconnect(TransportImpl.java:533)
net.schmizz.sshj.transport.TransportImpl.handle(TransportImpl.java:489)
net.schmizz.sshj.transport.Decoder.decode(Decoder.java:113)
net.schmizz.sshj.transport.Decoder.received(Decoder.java:200)
net.schmizz.sshj.transport.Reader.run(Reader.java:60)
```

**lib version:**

```shell
OS_ARCH="x86_64"
OS_NAME="Linux"
SOURCE=".:git:8f83880405cb"
BUILD_SOURCE="git:7c3aa6443f9d395b8603d37ebf8107e12bfc3e91"
BUILD_SOURCE_REPO="https://github.com/adoptium/temurin-build.git"
SOURCE_REPO="https://github.com/adoptium/jdk11u.git"
FULL_VERSION="11.0.19+7"
SEMANTIC_VERSION="11.0.19+7"
BUILD_INFO="OS: Linux Version: 5.15.0-48-generic"
JVM_VARIANT="Hotspot"
JVM_VERSION="11.0.19+7"
IMAGE_TYPE="JDK"
```

sshj:0.34.0

the same java client on windows server works:
OpenJDK 64-Bit Server VM; 11.0.4; 11.0.4+11; mixed mode

regards.