MNT Move config from silverstripe/admin so that unit-tests pass

_config/tests.yml

@@ -6,3 +6,16 @@ SilverStripe\Core\Injector\Injector:
     properties:
       States:
         debugSchema: '%$SilverStripe\GraphQL\Dev\State\DebugSchemaState'
+
+# This is added purely to prevent errors when running the unit-test IntegrationTest.php
+# This config used to be defined in silverstripe/admin with
+# on: [ graphqlSchemaBuild.admin ]
+SilverStripe\Core\Injector\Injector:
+  SilverStripe\EventDispatcher\Dispatch\Dispatcher:
+    properties:
+      handlers:
+        graphqlTranscribe:
+          # at least one handler is required to prevent an error
+          # it does not need to use ".unit-test" as a key
+          on: [ graphqlSchemaBuild.unit-test ]
+          handler: '%$SilverStripe\GraphQL\Schema\Services\SchemaTranscribeHandler'