Postgres connection pooling

[badgersrus]

Why this change is needed

Resolve this bug on dev

What changes were made as part of this PR

• Add connection pooling to postgres.go
• Duplicate the migration code due to trying to support the db *sql.DB as well through an interface results in needing to create a pgxpool.Pool wrapper and override the RowsAffected and LastInsertId methods

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[badgersrus]

Closing as this can be fixed through azure infra using PgBouncer.