DB connection pool is not used when creating new connections

[skudryav]

@yahonda We are seeing that @connection is different on every request even though pool size is 5

Steps to reproduce

Check that new db connection is created on every request and db connection pool is not used when creating new connections.

Expected behavior

Oracle Enhanced driver should have ability to use db connection pools (there is db connection pooling on OCI8/ruby)

Actual behavior

new db connection is created on every request - DB connection pool is not used when creating new connections

System configuration

Rails version:
6.1.7
Oracle enhanced adapter version:

= 6.1.5
Ruby version:
3.1.4
Oracle Database version:
19c