Remove unnecessary steps on doc about enabling HTTPS

Hi team,

I was following the [tutorial](https://goharbor.io/docs/2.5.0/install-config/configure-https/#deploy-or-reconfigure-harbor) to set harbor on my host.

For section "Provide the Certificates to Harbor and Docker" I find it may be unnecessary to provide your server certificate to docker client as it needs to install client certificate on "docker/certs.d/" directory only if when bi-directional authentication is needed for HTTPS. So for authentication only for server, I hold a question that is it fine to remove the following actions listed in tutorial.

```bash
openssl x509 -inform PEM -in yourdomain.com.crt -out yourdomain.com.cert # convert format
cp yourdomain.com.cert /etc/docker/certs.d/yourdomain.com/
cp yourdomain.com.key /etc/docker/certs.d/yourdomain.com/
```

BRs

kewei