[Cocoa]pods do not necessarily contain swift files/artifacts

[wagoodman]

Today the cocoapod cataloger always denotes the language for contained packages as Swift

syft/syft/pkg/cataloger/swift/package.go

Line 16 in 32296f5

Language: pkg.Swift,

which is not accurate since Cocoa applications only require a language that runs on the objective-c runtime (e.g. objective-c, swift, RubyMotion). For this reason we should either remove the hard coded language specifier or try and detect which language is contained within the package.

We should additionally rename the switft package to objectivec or similar (up to suggestions here).