CI: Add a workflow for checking binary size

[JurajSadel]

This workflow is triggered via comment with: /test-size.
It uses

on:
  issue_comment:
    types: [created, edited]

which complicates things a bit and that's why the workflow might be a bit hacky/ugly. To run properly, it firstly needs to be merged into main. I tested it on my fork JurajSadel#12.

closes #4304

[MabezDev]

I think a bit more work is required here. We have more than just .stack, .bss and .rodata so we should also be asking bloaty to check these. Also the formatting on the comments in your PR seem a bit off, layout-wise.

[JurajSadel]

I think a bit more work is required here. We have more than just .stack, .bss and .rodata so we should also be asking bloaty to check these.

This should be handled by bloaty I'm not specifying anything. I it shows sections when they are changed, when I didn't add anything to FLASH, .rodata was not printed. So I guess it should be fine 🤞

[JurajSadel]

Also the formatting on the comments in your PR seem a bit off, layout-wise.

I will play with this