Fix zimcheck warnings

[benoit74]

Zimcheck complains about tons of times:

    {
      "check" : "url_internal",
      "level" : "ERROR",
      "message" : "The following links:\n- ../../users/profiles/43968.webp\n(users/profiles/43968.webp) were not found in article users/43968/reid-evans",
      "links" : [
        "../../users/profiles/43968.webp"
      ],
      "normalized_link" : "users/profiles/43968.webp",
      "path" : "users/43968/reid-evans"
    },

This is "normal" errors because user images are not grabbed anymore and they are generated with JS.

We should probably find a workaround to not get these nasty zimcheck output which avoids to spot real problems which might exists as well. This could also be an opportunity to display a fallback image before switching to JS-generated picture, avoid the "broken image when JS did not yet ran" issue.

[benoit74]

Code to run zimcheck in Tests Github CI workflow mention other issues:

        # not using --redundant as user profile pics can be duplicates
        # not using --url_internal as zimcheck doesn't account for <base/> https://github.com/openzim/zim-tools/issues/250
        # not using --url_external as zimcheck doesn't account for <blockquote />, <script />, etc. https://github.com/openzim/zim-tools/issues/149

[benoit74]

This ticket is now supposedly only blocked by upstream issues:

• Invalid internal link error raised for template within <script> tag zim-tools#149
• zimcheck wrongly warns about external links which is plain text zim-tools#485

Issue around profile pics which can be duplicates is solved since we do not add profile pics anymore.

Issue around missing internal link on user profile images has been solved in #364

openzim/zim-tools#250 does not impact us anymore since we do not use <base/> anymore.