[POC] Fix documentation generation by internally filling the database configuration field

[koletzilla]

DO NOT MERGE, IT'S NOT SAFE.

This is just a POC to try to understand how many changes would be required to fix #311

The issue is related to our dbt-clickhouse not filling the database field on purpose. dbt uses database, schema and table to reference resources crates in the database but CH only uses 2, database and table. in dbt world, we are using instead schema and table and leave empty database to avoid errors.

This impacts tools that may want to process this information to build information systems.

In this PR I'm trying to see how we can fill the database configuration in some places so:

• 🟡 Users will still not configure it on purpose, only schema should be available and used
• 🟡 Code internally should NOT use the database field, only the schema is the one that needs to be used.
• ✅ The database (being the same name as the schema) is filled in catalog.json and manifest.json files son the database tab in the docs actually have data.

We need to make sure all these things are safe before moving forward with this PR

[koletzilla]

Note: as expected with this approach as mentioned here #311 (comment) , now some relations are wrongly named in the docs by including both schema and database parts like default.default.my_first_dbt_model