[ENH] Respect :exports none on source blocks

[hegde-atri]

Is your feature request related to a problem? Please describe.
Code blocks are shown even when I have :exports none, taking up unnecessary space.
I use org-babel to generate diagrams from source block which I neatly collapse in org-mode however this isn't the same with org-roam-ui

Describe the solution you'd like
Respect the :exports none header option on source code blocks.

Example of my problem. I just want the source block gone. It's okay if the results are also hidden, since I can just remove the #+RESULTS when I'm done.

[venikx]

For anyone wanting to implement this, I saw you are using uniorg-parse, and before the parsing step it didn't include switches and parameters. I needed this myself for my project that I'm working on, so I opened a PR: rasendubi/uniorg#91.