Removing redundant .swiftpm folder

[Rminsh]

The .swiftpm folder contains some xcode files that if you add the library to a project, it will add a new target scheme. This commit will prevent that situation.

[fermoya]

@Rminsh is that a folder that gets auto-generated? I use that folder to access the workspace and run tests there.

I've seen that some libraries don't commit this folder but other do commit it. If the problem is the target, you can always go to Manage Schemes and choose not to Show this framework?