Major projects cannot be submitted with the same name and repeated skills

Trying to resubmit a project with the same name and skills (a somewhat normal occurrence) fails due to how the creation of skills with MP ids work, which should be reworked so this does not happen.

(the problem child)
https://github.com/ComputerScienceHouse/conditional/blob/ebf825cdfabf89eec920d7e8173ec1070ce3d5c4/conditional/blueprints/major_project_submission.py#L125-L128

Start in conditional/blueprints/major_project_submission.py at lines 125-128, then reproduce submitting a major project with the same name and repeated skills. Trace how skills are created with major-project IDs; done means the resubmission succeeds without failing on those existing skills.

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