Move from psycopg2 -> psycopg3

[devhawk]

This PR moves our PG driver from psycopg2 to psycopg3. We are changing this because psycopg3 supports asyncio while psycopg2 does not.

Generally, the changes consisted of:

• changing host for db URLs from postgresql to postgresql+psycopg (note, the package name for psycopg3 is psycopg)
• changing PG error code field name from pgcode to sqlstate

Assorted other changes

• changed the psycopg specific code in _notification_listener to the psycopg3 API syntax
• cleanup exception handling in cases where we are re-raising a caught exception
• change CI/CD workflow to complete the entire python test matrix instead of failing fast on first error

[qianl15]

I updated the dependency to psycopg[c] instead of the binary one. https://www.psycopg.org/psycopg3/docs/basic/install.html#binary-installation

The reason is that there's no available binary for my laptop (macOS, M2 chip), which may affect our users as well.

Binary packages are produced on a best-effort basis; the supported platforms depend on the CI runners available to build the packages.