Add tolerations for model download job

[bd-g]

Proposed changes

The AWS model download job is coupled with the Engine deployment as currently implemented, and uses the same affinity. This fixes a scheduling issue by also adding the Engine tolerations block to that model download job, to avoid being blocked by node taints.

Types of changes

• Bugfix (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 not work as expected)
• Documentation update or tests (if none of the other choices apply)

Checklist

• I have read the CONTRIBUTING doc
• I have tested my changes in my local self-hosted environment
• I have added necessary documentation (if appropriate)

Further comments

Resolves #48