refactor(@vtmn/assets): delete sprite consumption mode

[lauthieb]

Changes description

Hello everyone,

We just spent a few hours with the designers of the core team Design System to understand the problem of using sprite with our Vitamin assets (flags, payments, etc.). In order to resolve it, we need to check all our different flags to remove masks & clip paths manually, and unfortunately, this is huge work & time-consuming which in regard to our team and the different priorities that we have, does not allow us to solve this soon.

That's why we took the decision to postpone the refactoring of all our flags in our next major release in design (@Decathlon/design-system-core-team-design), and so, we decided to no longer support the "sprite" consumption mode for @vtmn/assets.

So this PR can close #1313.

Thanks for your understanding.

Checklist

• [x] Make sure you are requesting to pull a topic/feature/bugfix branch. Please, don't request directly from your main!
• [x] Check commits & PR names match our requested structure. It must follow the https://www.conventionalcommits.org pattern.
• [x] Check your code additions will fail neither code linting checks.
• [x] I have reviewed the submitted code.
• [x] I have tested on related showcases.
• [x] If it includes design changes, please ask for a review design-system-core-team-design GitHub team.

Does this introduce a breaking change?

• No