Add end-to-end frontend testing using Cypress

[adelavega]

• Add comprehensive end-to-end frontend tests using Cypress
• Added to GH Actions
• Updated README to describe how to run tests locally using a development server / test database.

[adelavega]

These changes should allow for cypress to be run in headless mode, but to run in interactive mode, you need to run ./node_modules/.bin/cypress install to install cypress locally.

[codecov-io]

Codecov Report

Merging #847 (60adf17) into master (796f12d) will decrease coverage by 0.05%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##           master     #847      +/-   ##
==========================================
- Coverage   84.68%   84.62%   -0.06%     
==========================================
  Files          57       57              
  Lines        2827     2829       +2     
==========================================
  Hits         2394     2394              
- Misses        433      435       +2     

Impacted Files	Coverage Δ
neuroscout/config/example_app.py	0.00% <0.00%> (ø)

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[cypress]

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Test summary

7 • 0 • 0 • 0

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Run details

Project	Neuroscout
Status	Passed
Commit	570551d
Started	Jan 20, 2021 12:08 AM
Ended	Jan 20, 2021 12:09 AM
Duration	00:42 💡
OS	Linux Ubuntu - 18.04
Browser	Electron 87

View run in Cypress Dashboard ➡️

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This comment has been generated by cypress-bot as a result of this project's GitHub integration settings. You can manage this integration in this project's settings in the Cypress Dashboard

[cypress]

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Test summary

7 • 0 • 0 • 0

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Run details

Project	Neuroscout
Status	Passed
Commit	0e32f17 ℹ️
Started	Jan 20, 2021 12:08 AM
Ended	Jan 20, 2021 12:09 AM
Duration	00:43 💡
OS	Linux Ubuntu - 18.04
Browser	Electron 87

View run in Cypress Dashboard ➡️

---

This comment has been generated by cypress-bot as a result of this project's GitHub integration settings. You can manage this integration in this project's settings in the Cypress Dashboard

[adelavega]

Things left to do:

• Finish Report tab API stub
• Avoid calling by class name in tests if possible
• Add comments to tests
• Avoid using visible tag if possible
• @rwblair review my tests

For future test coverage:

• OAuth2 tests?
• Test Analysis Browser (public/private)
• Test Predictor Upload

[adelavega]

Merge master and test all is working as well