fix(settings): connections includes props from core

closes #1066

src/runtime/schema/settings.spec.ts

@@ -1,3 +1,4 @@
+import { cloneDeep } from 'lodash'
 import { createSchemaSettingsManager, SchemaSettingsManager } from './settings'
 
 let sm: SchemaSettingsManager
@@ -25,3 +26,11 @@ it('has defaults', () => {
     }
   `)
 })
+
+describe('connctions', () => {
+  it('can be changed, preserving the core defaults', () => {
+    const original = cloneDeep(sm.data)
+    sm.change({ connections: {} })
+    expect(sm.data).toEqual(original)
+  })
+})

src/runtime/schema/settings.ts

@@ -146,11 +146,7 @@ export function changeSettings(state: SettingsData, newSettings: SettingsInput):
   }
 
   if (newSettings.connections) {
-    // todo deep merge
-    Object.assign(state.connections, {
-      ...newSettings.connections,
-      ...connectionPluginConfigManagedByNexus,
-    })
+    Lo.merge(state.connections, newSettings.connections)
   }
 }