make trim images script more robust

[djones1040]

Fixes # . Issue #267

Description of the Change

image trimming was having some issues with non-overlapping and weirdly damaged images. put in a couple failsafes to catch these exceptions, though might not be perfect. Affects the trim_transient_images system task

Checklist

Please check all that apply to your proposed changes

• [ ] HTML code change
• [ ] Added package dependency
• [ ] Added data
• [ ] Changed django model
• [ ] Documentation change
• [x] Added or changed TaskRunner

Additional context