fix: standardize source files type and remove __unused from types

[edusperoni]

the change to autolink-info fixes an issue where if a package specifies a single string as source files, open native would fail to link it

For example:

source_files: someFiles/**

when doing [...commonSourceFiles, the result would be: ['s', 'o', 'm', 'e'..... So now we standardize the type as always an array of strings.

The change to method solves the issue where the type would start with __unused when it was left by the package developer (in this case @react-native-community/netinfo)