### Is there an existing issue for this?

- [X] I have searched the existing issues

### Current Behavior

We are using the `Authorization` header for routing purposes

```
 "authorization: AWS4-HMAC-SHA256 <...>"
```

https://github.com/localstack/localstack/issues/5770

### Expected Behavior

Use a custom header to avoid causing confusion with backend integrations

### How are you starting LocalStack?

With a `docker run` command

### Steps To Reproduce

Run a custom HTTP integration without authorisation

### Environment

```markdown
- OS: 
- LocalStack:
```


### Anything else?

No
"""Simple duplex socket wrapper that allows serving HTTP/HTTPS over the same port."""
    def accept(self):
        newsock, addr = socket.socket.accept(self)
        if DuplexSocket.is_ssl_socket(newsock) is not False:
            newsock = self.context.wrap_socket(
                newsock,
                do_handshake_on_connect=self.do_handshake_on_connect,
                suppress_ragged_eofs=self.suppress_ragged_eofs,
                server_side=True,
            )
        return newsock, addr
    @staticmethod
    def is_ssl_socket(newsock):