Rework Expenses resource (#3)

Co-authored-by: Joe Arndt <jmarndt@users.noreply.github.com>
Reviewed-on: #3

src/expenses/dto/update-expense.dto.ts

@@ -0,0 +1,6 @@
+import { PartialType } from '@nestjs/mapped-types';
+import { CreateExpenseDto } from './create-expense.dto';
+
+export class UpdateExpenseDto extends PartialType(CreateExpenseDto) {
+  id: string;
+}