Ugly error when the repo uses podspec or cartfile

[chrismwendt]

langserver-swift/Sources/LanguageServerProtocol/Types/WorkspaceError.swift

Line 38 in 274ea09

return "Could not find \(url.path) in the workspace."

Could not find ... in the workspace.

I think this happens because some repos use .podspec or Cartfile instead of Package.swift. A nicer error message would be ✨