TisserantG

## What does this PR do ? Add virtual tenant ### How should this be manually tested? See functionnal test ### Other changes js -> ts for many files

## Expected Behavior exists must work like example in : https://docs.kuzzle.io/core/2/api/koncorde-filters-syntax/clauses/#matching-array-values ## Current Behavior Following https://docs.kuzzle.io/core/2/api/koncorde-filters-syntax/clauses/#matching-array-values I do : ``` const filter = { query: { "exists": 'name.hobbies["compiler"]' } }...