Reject "Missing images" in sensor-dicoms

[chaselgrove]

This catches the interrupted scans we've been encountering.

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Comparison is base (31d4b97) 81.97% compared to head (98a1f29) 81.97%.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #735 +/- ## ======================================= Coverage 81.97% 81.97% ======================================= Files 41 41 Lines 4149 4149 ======================================= Hits 3401 3401 Misses 748 748 ```

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[github-actions[bot]]

:rocket: PR was released in v1.0.2 :rocket: