swift: generate xcode project fails with "libraray not loaded"/"image not found"

Hi,
I am new to exorcism. I am trying to complete the first hello world project, but I am having trouble with the instructions that was given. Here are the instructions from the website.
"In the Terminal cd to the directory for an exercise (for example, ~/exercism/swift/exercises/hello-world/), then execute swift package generate-xcodeproj. This creates an Xcode project in the current directory with the same name as the package. (The generated project is ideal for unit tests. It does not include the overhead of launching the iOS simulator or a target application.)"

For some reason when I try to execute swift package generate-xcodeproj, I get:

```plain
dyld: Library not loaded: @rpath/llbuild.framework/Versions/A/llbuild
  Referenced from: /Library/Developer/CommandLineTools/usr/bin/swift-package
  Reason: image not found
Abort trap: 6
```

Can someone please help.

Reproduce the failure by running `swift package generate-xcodeproj` from the Swift hello-world exercise directory. Start with the reported `/Library/Developer/CommandLineTools/usr/bin/swift-package` dyld error and the quoted instructions; the work is done when the cause and a verified correction to the instructions or setup are documented.

Written by the indexing model from the issue text.