Problem: No AMAUAT tests the content/structure of AIP METS

[sromkey]

Please describe the problem you'd like to be solved.
A time consuming part of manual regression testing is ensuring that the AIP METS contains expected content and structure. We could have an Archivematica Automated User Acceptance Test that defines and tests the criteria for what should be in the AIP METS.

Describe the solution you'd like to see implemented.

1. Describe what an AIP METS should look like/contain
2. Write a feature file and test for that criteria.

Additional context
Requirements are being gathered here: https://docs.google.com/spreadsheets/d/1EbCshlXUPWYb1bBFxz5ObA4FHxWCkcJf38nCYGgVhCI/edit#gid=1934959319

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[ross-spencer]

Completed as part of our work with @wellcometrust. Epic here.