[FIX] website: ensure websites have snippet filters

[rdeodoo]

Since the feature was implemented with the default snippets having a website_id
set to the default website, it means that every other websites won't have
snippet filters.

This commit bootstrap filters for every new created website.

Note that in master, multi-website and generic filters are handled with
550d293.

opw-2381423

[rdeodoo]

@JKE-be Can you have a first look to see if that's the way you want it to go?

The backport commit should be enough to fix when the user do a -u (its backport + set website_id to False)

For when no -u, the other commit should handle cases of creating a new website, removing the default website.

But one issue remain: User do not -u, delete the default website (filters are lost), then create a new website (no filters).
Solution : Since no -u, we can't play with ondelete or required so maybe we prevent delete of default website while the user hasn't done -u, or we hardcode in python the creation of the default filters instead of copy, again only if no -u

[rdeodoo]

As a reminder since those messages are folded, the forward port is disabled, so this is just for 14.0.
The fix typo commit will be cherry picked in #62409

[rdeodoo]

@JKE-be Fixed the right error for non admin user

[JKE-be]

@robodoo r+

[robodoo]

Because this PR has multiple commits, I need to know how to merge it:

• merge to merge directly, using the PR as merge commit message
• rebase-merge to rebase and merge, using the PR as merge commit message
• rebase-ff to rebase and fast-forward

[JKE-be]

@robodoo rebase-ff

[robodoo]

Merge method set to rebase and fast-forward