Add Support for DuckDB

[naiyerasif]

DuckDB is a very popular analytical database which follows SQL dialect similar to Postges with minor exceptions.

Currently, JdbcTemplate works if I stay close to Postgres dialect while using DuckDB but cracks begin to show when I try to use DuckDB-specific syntax. Also, by default, Spring Data refuses to load the DuckDB datasource through configuration file, throwing UnsatisfiedDependencyException even when the DuckDB driver is on classpath, forcing me to fallback to programmatic datasurce initialization.

This request is to add support for the following:

• When spring.datasource.url=jdbc:duckdb:, Spring Data should assume DuckDB to be running in in-memory mode and use in-memory semantics (such as turning spring.sql.init.mode=always) to initialize a datasource bean.
• When spring.datasource.url=jdbc:duckdb:/tmp/my_database, Spring Data should assume DuckDB to be running in persistent mode and use the default semantics to initialize a datasource bean.
• An official dialect support would be fantastic but at the very least JdbcTemplate should not throw exception for DuckDB specific syntax.

[mp911de]

We don't have the bandwidth to support more databases.
Please consider hosting the dialect in a separate repository.

We hope to eventually provide support for testing new dialects.

See: #2048