Add tests for rake tasks

Overview

Currently, only the object_store:setup rake task is tested in this repo: spec/tasks/object_store_spec.rb. We want to add tests for other rake tasks as mentioned at !3822 (comment 1993470736).

Impacted categories

The following categories relate to this issue:

• gdk-reliability - e.g. When a GDK action fails to complete.
• gdk-usability - e.g. Improvements or suggestions around how the GDK functions.
• gdk-performance - e.g. When a GDK action is slow or times out.

Steps to replicate (optional)

Proposal (optional)

Environment (optional)

• Operating system name: <!-- output of `uname -a` command -->
• Architecture: <!-- output of `arch` command -->
• The contents of your gdk.yml (if any)
• Ruby version: <!-- output of `ruby --version` command -->
• GDK version: <!-- output of `git rev-parse --short HEAD` command -->