Uniformize system that exclude some articles routes

[julien-deramond]

Description

Some articles routes are excluded from the OG image generation, rendering of the progress scroll and reading time.
Almost the same, or the same, condition is copy-pasted at 3 different places and is not very handy to maintain.
The goal of this issue would be to store that in some reusable in the code.

The corresponding files can be found at https://github.com/Open-reSource/openresource.dev/pull/925/files