Export relationships query clients and allow instanceName config property

Features

• export relation's query client (#1061) (597cf40)

What's Changed

• Add missing instanceName to the MssqlConnectionNode type by @Imunal in #1063
• feat: export relation's query client by @adamcikado in #1061

New Contributors

• @Imunal made their first contribution in #1063

Full Changelog: v21.3.0...v21.4.0