sql: convert SQL constraints to core constraints

This patch converts existing SQL foreign key constraints and check
constraints into core foreign key constraints and check constraints.

Closes #6986

@TarantoolBot document
Title: SQL constraints

SQL constraints will now use the tuple constraint mechanism instead of
the original SQL mechanism. This allows to set constraints that are
independent of the language used for creation. However, this disables
some SQL constraint features that are not supported by tuple
constraints.