Localize links to docs.qgis.org (or other) when possible

[nboisteault]

We must use links to docs.qgis.org when possible to avoid duplication of efforts.

If would nice to localize links, for example https://docs.qgis.org/latest/en/docs/index.html would be transformed to https://docs.qgis.org/latest/fr/docs/index.html in french documentation.