Set up test data and add basic tests for app conformance

[jaeddy]

from @jaeddy to @thomasyu888 on Slack:

this might be somewhat cumbersome to set up initially, but i think would be easier to adapt/extend moving forward (and you could probably get it working a lot more quickly than me anyway):

1. There are 3 files and instructions for how to validate/upload manifests here; along with another for publications attached
2. if you were to subset those (maybe not the additional_standard_terms sheet...), then do a Synapse tableQuery to grab the matching rows from the Publications, Datasets, and Tools and pull the CSVs/dfs
3. ideally, there should be a way to run a test for each of the manifest files without needing to use the app itself or upload the final results to Synapse (e.g., my comparing the ready-to-upload data to the CSV/df rows)
4. if everything matches, then you at least know that the tool is still working the same after your changes
5. if they don't match, then we'd need to take a closer look... in case you actually fixed a bug somewhere