chore: Enfore consistent file-name casing on all backend packages (#15755)

packages/@n8n/di/src/__tests__/fixtures/service-a.ts

@@ -0,0 +1,8 @@
+// eslint-disable-next-line import/no-cycle
+import { ServiceB } from './service-b';
+import { Service } from '../../di';
+
+@Service()
+export class ServiceA {
+	constructor(readonly b: ServiceB) {}
+}