[IMP] sales: invoice status on SOs

[ksc-odoo]

PROJECT TASK: https://www.odoo.com/odoo/project.task/4001061?cids=3

As requested in the Project Task, this PR adds information about the Invoice Status field on a Sales Order, which only appears in Debug mode.

It also adds an explanation about the Invoicing Journal field that appears in Debug Mode, as well.

Felt obligated to add the Invoicing Journal information because that is the only other field that appears in the Invoicing section of the Other Info tab (with Debug mode on)

[robodoo]

[ksc-odoo]

Hey @larm-odoo -- this one's ready for a Peer Review from you (whenever you get a chance). Thanks.

[ksc-odoo]

Ok. I've made the necessary adjustments, and believe this is ready for another look, @larm-odoo 🙏

[ksc-odoo]

Thanks for the helpful feedback, @larm-odoo -- really appreciate it 🙏 -- Looks like this quick PR is ready for a Final Review, @StraubCreative (whenever you get a chance). Thanks! 👍