Implement the picodata engine for sbroad to integrate distributed
SQL into the picodata binary. In fact, picodata engine simple
exports public rust functions from api.rs. On the picodata side
they (and some lua functions) are imported and included into the
bunary on the build phase.

Current commit is POC and have some problems:
- DDL is still not implemented in the picodata (_pico_space is mocked);
- we include tarantool module symbols twice (first time in sbroad,
  second time in picodata binary);

But anyway, it works and all these problems should be solved in the
next commits.

We had a flaky test in CI because printing order
of keys in Distribution::Segment was random.
Changed Hasher to RepeatableState for HashSet
in Distribution::Segment

The traits to plug new engines became more clear. It would help us
while implementing the picodata engine.

tarantool uses async replication by default, and it is possible to try selecting from a replica that does not have the space or the data yet, which can cause flaky tests
now, we configure storage replicaset and enable sync replication for spaces to work with
Closes #369

Previosly we had a very complicated logic for INSERT operator:
we always generated a motion node under INSERT and generated
bucket_id with a special motion command in this virtual table.
As a side effect we made motions even for those INSERTs that was
possible to execute locally.

Another problem was caused by the column type derivation in
INSERT .. VALUES .. expressions. If any column in the first row
contained NULL it confuses Tarantool and it returns scalar (or
even boolean!) type instead. And there is no projection type cast
in Tarantool's insertion. As a result we often had type mismatch
errors in INSERT .. VALUES .. queries.

The solution is to rewrite this weird logic from the scratch.
Now we rewrite the tree somehow like this:

insert into t1 (a, b) values (1, 2)

=>

insert into t1 (a, b, bucket_id)
select
  COL_1,
  COL_2,
  bucket_id(
    coalesce(cast(COL_2 as string), '')
    || coalesce(cast(COL_1 as string), '')
  )
from (
  select
    cast(COLUMN_1 as integer) as COL_1,
    cast(COLUMN_2 as unsigned) as COL_2
  from (values (1, 2))
)

- added count, sum aggregates, which can be used in queries with group by

currently we mean expression with arithmetic, bool and
unary operations by arbitrary expr