Fix and optimize license check workflow logic

[rauljzortega]

Fix logic in check_licenses.yml to prevent errors in merge/push events.

[ocaisa]

I'm looking at some of the results from the licenses check and wondering why the CI is not failing for them:

...
Underworld:
  2.16.4:
    License: not found
    Permission to redistribute: false
    Retrieved from: not found
aiohttp:
  3.9.5:
    License: not found
    Permission to redistribute: false
    Retrieved from: not found
debugpy:
  1.8.1:
    License: not found
    Permission to redistribute: false
    Retrieved from: https://aka.ms/microsoft/debugpy/blob/main/LICENSE
deprecation:
  2.1.0:
    License: not found
    Permission to redistribute: false
    Retrieved from: not found
ipywidgets:
  8.1.2:
    License: Other
    Permission to redistribute: false
    Retrieved from: https://jupyter.org/
jupyter-server:
  2.14.0:
    License: Other
    Permission to redistribute: false
    Retrieved from: https://jupyter.org/
...

all of these are clearly a problem, but the CI is not flagging them at all.

[ocaisa]

Ah, I see it generates a patch file...but perhaps it should actually fail when we do not have permission to redistribute and provide advice about what to do? The current CI will never fail, so no-one will pay attention to problems being introduced.

[ocaisa]

Also, ipywidgets is BSD 3-Clause which is the common licence for Jupyter, why is it picking up Other?