This is temporary to avoid a dependency conflict that arises in `libsqlite3-sys`

The two DBMs are now in use, this is an intermediary commit and `dbm.rs` should be deleted and replaced with `dbm_new.rs`, and the tower components should be adjusted accordingly (drop the mutex around the dbm since the pool handles it by itself & await on dbm methods since they are now async)

Some mutexed needed their lifetimes be shortened due to the fact that an std mutex guard can't live across await point. one specific mutex on GateKeeper::registered_users was more fitting to be a tokio mutex instead due to the nature of how it is uses beside the database usage (std mutex is generally better/has less overhead than a tokio mutex).

tests still need to be patched for async

Postgres tests are still not working because with each test we need to spawn a brand new database (best done inside a docker container) from within the tests

this still needs an external test db running on the background. one can easily be spawned with docker

remove rusqlite dependency from teos-common