YQL-20631: Support simple CTEs on YqlSelect

The first iteration on WITH CTE support. Only simple CTEs are supported.

Properties:

1. Redefinition is forbidden.

2. Shadowing is supported.

3. Nested WITH CTEs are supported.

Following features are not yet implemented:

1. Column names specification. There is an assertion failure at core because
   of an absent column order when translating it like for the `PgSelect`.

2. `RECURSIVE` is postponed. There a more sophisticated translation with
   `YqlSelf` callable is required.

Also there was a potential defect because of an empty `Id` result not expected.
commit_hash:759676d8a9d369f7eedd9b87f79455b2f8a9fcff

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