We are updating to Train 3.x across the Workstation/DK, ensure this gets bumped

[tyler-ball]

Description

train-core stays at 2.1.19 for now because that is a transitive dep of chef. Once we update chef to >= 15.3 train-core will update to >= 3.0. Since they are split out as train vs train-core there is no conflict, and train-core is just a subset of train.

Related Issue

N/A

Types of changes

• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)
• [x] Chore (non-breaking change that does not add functionality or fix an issue)

Checklist:

• [x] I have read the CONTRIBUTING document.
• [x] I have run the pre-merge tests locally and they pass.
• [x] I have updated the documentation accordingly.
• [x] I have added tests to cover my changes.
• [x] All new and existing tests passed.
• [x] All commits have been signed-off for the Developer Certificate of Origin.