Bitrise Collect Artifacts step.
This step collects build artifacts from all builds started using the Bitrise Start Build step (https://github.com/bitrise-steplib/bitrise-step-build-router-start)
This step will use the Bitrise API (https://api-docs.bitrise.io/#/) to download the build artifacts from each of the build slugs set in the $ROUTER_STARTED_BUILD_SLUGS
output generated by the Bitrise Start Build step.
Each build artifact can be saved into a custom path.