Fix formatting and link references in integration testing topic outline

[daaimah123]

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Page where problem found?

• Integration Testing

Type of problem

There are presently multiple areas in the integration testing topic outline that look like htey may be missing reference links or need to be expanded upon. For example, in the Supplemental Materials section there are bulleted items listed as

• [Testing a Database][db-testing-alt] — this discusses an alternate approach to DB testing than we'll take at a very high level.
• [node-postgres structure suggestion][postgres-structure]
• [The Express API][express-api]
• [superagent api][superagent-home] — this is the API underlying supertest
• [Using PostgreSQL with Node.js][nodejs-postgres] — A simple example of using PostgreSQL within the context of a Node.js project (not Express which does have some impact) [postgres-structure]: https://node-postgres.com/guides/project-structure [express-api]: https://expressjs.com/en/4x/api.html [nodejs-postgres]: https://linuxhint.com/postgresql-nodejs-tutorial/

Acceptance Criteria

• Address this formatting and / or add respective links (such as references to existing curriculum links based on the bracketed string written)
  • Before - [The Express API][express-api]
  • After - The Express API
• Any bracketed strings with a colon followed by a link needs to change the formatting to have bracketed words be linked to the referenced url and bracket removed:
  • Before - [postgres-structure]: https://node-postgres.com/guides/project-structure
  • After - postgres-structure