[chore] drop dev. dependencies that are leading to errors on running `npm install` in this repo

### Is there an existing issue for this?



- [X] I have searched the existing issues



### Current behavior



we can't use `npm install` after cloning https://github.com/nestjs/nest repo due to this error:



![image](https://github.com/nestjs/nest/assets/13461315/c9ba6e57-09b6-41e8-9067-6899fbf792ef)



which is related with legacy packages:

- `commitlint-circle` -- the last update was 6 years ago

- `merge-graphql-schemas` -- this [has been deprecated](https://www.npmjs.com/package/merge-graphql-schemas)



After removing them from our deps list and after resolving the PR https://github.com/nestjs/graphql/pull/3181 (to support the latest `ts-morph` on `@nestjs/graphql`), `npm install` will work as expected.



I didn't fully understand why those dependencies are needed. So if they are, ignore this issue.



```bash

git clone git@github.com:nestjs/nest.git

cd nest

npm i

## see the error

```



### Expected behavior



Install the deps without the need to use the flag `--legacy-peer-deps`



https://github.com/nestjs/nest/blob/6f119a7fdd46718327d3e1f4cb0bdc5d0ac7531b/.circleci/config.yml#L32

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