Refactor translation reports collection and Gatsby source plugin

[pdcp1]

Part of #3289

Summary

• Add migration to move the translations to a single reports collection under translations DB
• Refactor landing page to use gatsby consolidated translations query for reports
• Add gatsby-source-mongodb plugin for the new "reports" collection in translations database
• Refactor citation page creation to streamline translation handling and simplify Gatsby GraphQL queries

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 97.17%. Comparing base (9fe3ac5) to head (8ca6b6c).
Report is 2 commits behind head on staging.

Additional details and impacted files

@@           Coverage Diff            @@
##           staging    #3290   +/-   ##
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  Coverage    97.17%   97.17%           
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  Files           60       60           
  Lines        12334    12334           
  Branches       308      308           
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  Hits         11986    11986           
  Misses         334      334           
  Partials        14       14           

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[pdcp1]

Closing this PR in favor of:

• [Translations] 1 - New single Reports translation collection #3302
• [Translations] 2 - Gatsby graphql queries refactor #3303