Web API: update `graphql-java` 13.0 dependency to newest stable one

[jhou-pro]

Description

Our current graphql-java dependency has vulnerabilities. Also GraphQL specification has been evolved. We need to update our Web API implementation to conform to most recent specification and non-vulnerable internals.

• [x] Specification does not support Long / BigDecimal scalars -- define custom ones to support TG types (e.g. as for Money / Date)
• [x] ValuesResolver made more private and API changed -- sync with these changes
• [ ] Fetching of entity-typed subproperty of collectional property don't work on most recent stable 21.3 graphql-java
• [ ] to be continued...

Expected outcome

Up-to-date TG Web API GraphQL-based implementation with no vulnerabilities.