Do not overwrite cwd if knexfile and cwd is passed

[petar-lazarov]

When having both --cwd argument and --knexfile argument, the knexfile basepath overwrites the process cwd which is strange IMO.

If we pass --cwd it should have higher precedence than the basepath of the --knexfile for process cwd selection.

My use case for knex is strange. I'm trying to integrate it in firebase project and I want the configuration values for password and username to be loaded by firebase runtime configuration.

The file structure looks like this

.
├── src
│   ├── migrations
│   │   └── ...
│   ├── index.ts
│   ├── knexfile.ts
├── .runtimeconfig.json

I wanted the knexfile.ts and migrations to be under src directory but the .runtimeconfig.json should be in the parent directory and it contains the values for those variables.

When I execute from .:

knex --knexfile src/knexfile.ts --cwd . migrate:status

the working directory is initially . but after that it is overwritten by ./src/.

You cannot tell to firebase where to find its .runtimeconfig.json. It always search for it in the current working directory I think.

I found two pull requests that are related to that topic and based on this PR #3613 and the table which was created by @briandamaged (https://docs.google.com/spreadsheets/d/19TMouhxdIosYGzubO-2lbxm8Ykx4jR-Iu74HXohFYMg/edit#gid=0) I realised that this might be a bug which I think was introduced by PR #4122.