Feature/tests and node version

[apricot13]

This PR:

• adds in the same mongo permission fixes from Outpost (the .docker/services/* folder is designed to be shared between the projects
• adds in code coverage
• adds a lot more tests
• upgrades outpost-api from node 16.18.0 to lts/iron
• restructures the application to make it more testable but also easier to document and understand
• added logging and optional logging levels
• DATABASE_URL is now DB_URI
• ⚠️ now only accepts AND queries, sending taxonomies=cat&taxonomies=dog will no longer return cat or dog results, it will return results that have both cat AND dog
• added 'score' to the results for ordering, results are now returned in updated_at, keyword score match or distance_from order

[codecov-commenter]

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