Translate 404, 500, 422 errors pages

[jibees]

What? Why?

Closes #9492

What should we test?

• The aim is to test the errors page, they should be the same as previous by default, and can now be translated via keys:
  • .errors.(not_found|internal_server_error|unprocessable_entity).title for the title,
  • .errors.(not_found|internal_server_error|unprocessable_entity).message_html for the content of the page
• Errors pages can be access via /404, /500 and /422 and I can imagine that they should be displayed if any errors (type 404, 500, 422) occurs.

Release notes

Changelog Category: User facing changes

[mkllnk]

Great! I just thought of one little issue.

[filipefurtad0]

Yaayy the 😸 is back!

On the pics below:

• left staging-FR, master staged
• right staging-UK this PR staged

Some comments

• from the pics above, it can be seen that before staging the URLs /500 /404 /422 all trigger a 404 error in the console;

• after staging we can see that the URLs /500 /404 /422 trigger the respective error in the console ✔️

• The pages render correctly so think these can be translated into other languages once the locales have been updated ✔️

• It was also verified that these files are correctly displayed, when the respective errors are triggered in the app ✔️

  • 404 - OK
  • 500 - OK
  • 422 - err I'm not sure how to catch this one any more...

This all looks good to me - thanks @jibees ! 🎉