Incorrect ssh command syntax

[swapdisk]

Describe the bug
When setting the ssh_command var with a destination port number, the command syntax is incorrect.

To Reproduce
Steps to reproduce the behavior:

1. Deploy a config that provisions an environment including an ssh command example for connecting to a specific port number, for example, a RHEL lab hosted on CNV.
2. Observe that the ssh_command var is set using ssh user@destination -p port syntax.

Expected behavior
Use correct ssh command syntax as found in OpenSSH documentation. This could be either:

1. The traditional command syntax with options first followed by user@hostname destination, that is ssh -p port user@destination, or
2. The more modern way using a destination URI like ssh ssh://user@hostname:port.

The URI syntax was introduced in 2018 with OpenSSH 7.7, so surely that should be good for everybody today.

Affected code

• ansible/configs/base-infra/post_software.yml
• ansible/roles/bastion-student-user/tasks/main.yml
• ansible/configs/zero-touch-base-rhel/post_software.yml

Additional context
My preference would be the more modern URI syntax, but happy to consider community input.

Unless there are any objections, I'll open a PR for this.