Prevent having to match database queries

[ra0x3]

• After New sqlite support #134 we now have support for two database types: Postgres, Sqlite
• Each database is currently split into it's own crate
  • They behave very similarly but have some slight differences
• Currently when having to execute a statement, we're match'ing the database type
  • Here is an example
• This works fine, but requires quite a bit of boilerplate (especially for slightly more involved queries)
• It would be great if we could create a proxy component that uses a single interface to interact with the data layer, regardless of which database is being used

Additional context:

So instead of:

• This is already done in fuel-indexer-schema/db/models.rs
  • But maybe this more properly belongs in fuel-indexer-database ?
• The idea is to abstract the match'ing boilerplate to a lower level
• This appears to be an open sqlx question/issue