Fix: Remove AS Keyword for Subquery Aliases in Oracle SQL

[tolebiermekov]

Oracle SQL does not permit the use of the AS keyword when aliasing subqueries. While AS is valid for column and table aliases in some contexts, subquery aliases must not include the keyword AS. This PR addresses this limitation in the SQLTableCheckOperator.

Changes:
Updated the SQLTableCheckOperator to handle Oracle-specific SQL syntax by omitting the AS keyword for subquery aliases.
Introduced a check to determine the database type, ensuring this adjustment is applied only for Oracle SQL.
Added relevant unit tests to ensure compatibility across supported databases.
Closes:
Closes #44135.

Notes:
This change ensures that Airflow's SQLTableCheckOperator works seamlessly with Oracle SQL while maintaining compatibility with other databases.

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[potiuk]

Nope. This is still very wrong. "common" sql provider should not know anything about "oracle" - this is the main reason why we introduced "common.sql" and all the "database" specific calls should come to the provider - so you have to modify it in the way that all "oracle" specific code lives in the "oracle" provider. You should implement a new feature in the common.sql where you can replace the template and then make oracle provider to replace it.