Removes unused masses and related checking functions in systems_design

Removes unused masses and related checking functions

Testing Instructions

1. Check that MME error is gone

Developer Checklist

• Code has been tested locally and/or in pipeline.
• (if applicable) documentation updated.
• (if applicable) impact of new dependencies reviewed and included in project.
• Merge conflicts resolved with the target branch.

added modulesystems_design label

requested review from @Florian.Schueltke

assigned to @ellen.seabrooke

approved this merge request

mentioned in commit 0cd820a9

merged