Error when using Xcode 13.4 / Swift 5.6

I'm getting the following error after updating my GitHub Actions workflow to use Xcode 13.4:

Cloning and building inline dependencies: import DangerSwiftCoverage // package: https://github.com/f-meloni/danger-swift-coverage.git, this might take some time.
Updating packages...
Using https://github.com/f-meloni/danger-swift-coverage.git latest major:1
Updating packages...
ERROR: keyNotFound(CodingKeys(stringValue: "object", intValue: nil), Swift.DecodingError.Context(codingPath: [], debugDescription: "No value associated with key CodingKeys(stringValue: \"object\", intValue: nil) (\"object\").", underlyingError: nil))

To reproduce, include this in your workflow:

jobs:
  MyDangerJob:
    runs-on: macos-12
    env:
      DEVELOPER_DIR: "/Applications/Xcode_13.4.app/Contents/Developer"
    ...

Any ideas how to resolve this?