Improve dev-exp for testing locally linked external sdk-dependent libraries

Right now the way to test a locally-linked library (that uses it's own package of `@dcl/sdk`) before publishing the library in npm is kind of messy and involves several steps that have to be run in a specific order:

1. scene: `npm install`
2. local utils library: `npm install`
3. local utils library: `npm link @dcl/ecs [PATH TO SCENE]`
4. local utils library: `npm run build`
5. local utils library: `npm link`
6. scene: `npm link @dcl-sdk/utils`
7. scene: `npm run start`

That's because the @dcl/sdk library used in the library gets built in the library itself and, when the library is used, it references a different engine than the one used in the scene.

There should be an easier and more direct way to test locally linked libraries that use `@dcl/sdk`