[Bug]: Inconsistent MYSQL connection string requirements

[hibare]

What steps did you take and what happened:

If we are using external MySQL and pass connection string as ARCHIVISTA_SQL_STORE_CONNECTION_STRING=root:example@db/testify will result in app startup error

archivista-1  | May 14 10:32:49.581 [INFO] SQLStoreConnectionString: root:example@db/testify
archivista-1  | May 14 10:32:49.581 [INFO] SQLStoreBackend: MYSQL
archivista-1  | May 14 10:32:49.581 [FATA] could not create ent client: could not parse mysql connection string: default addr for network 'db' unknown

And if we decide to pass connection string as root:example@tcp(db)/testify will result in atlas failure.

archivista-1  | Running migrations for MySQL
archivista-1  | ARCHIVISTA_SQL_STORE_CONNECTION_STRING: root:example@tcp(db)/testify
archivista-1  | Error: mysql: query system variables: dial tcp: lookup tcp(db): no such host
archivista-1  | Failed to apply migrations

What did you expect to happen:
When connection string is set as ARCHIVISTA_SQL_STORE_CONNECTION_STRING=root:example@db/testify, expect normal app startup

Anything else you would like to add:

There is an open issue on mysql driver repo go-sql-driver/mysql#1074 for same.

Environment:

• Witness version:
• Architecture:
• Attestors used:
• Archivista version: