BugFix/Patch: PostGreSQL Record Manager

[Nek-11]

In #4381 I proposed a fix for time handling and schema creation in PostgresRecordManager.

However, I made a mistake there. The CREATE EXTENSION IF NOT EXISTS pgcrypto; line causes failures on Azure Database for PostgreSQL Flexible Server where such commands are blocked, even if the extension is already installed. Therefore, this PR removes that line.

It also updates the getTime() query to use AS extract instead of AS now, in order to preserve 100% backward compatibility with existing code that expects res[0].extract.