Bump express and @nestjs/platform-express in /blog-backend

Bumps [express](https://github.com/expressjs/express) to 4.18.2 and updates ancestor dependency [@nestjs/platform-express](https://github.com/nestjs/nest). These dependencies need to be updated together.


Updates `express` from 4.17.1 to 4.18.2
- [Release notes](https://github.com/expressjs/express/releases)
- [Changelog](https://github.com/expressjs/express/blob/master/History.md)
- [Commits](expressjs/express@4.17.1...4.18.2)

Updates `@nestjs/platform-express` from 6.10.8 to 9.2.1
- [Release notes](https://github.com/nestjs/nest/releases)
- [Commits](nestjs/nest@v6.10.8...v9.2.1)

---
updated-dependencies:
- dependency-name: express
  dependency-type: indirect
- dependency-name: "@nestjs/platform-express"
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>