Persist osm login across playwright tests (temp login removed)

[spwoodcock]

What type of PR is this? (check all applicable)

• 🍕 Feature
• 🐛 Bug Fix
• 📝 Documentation
• 🧑‍💻 Refactor
• ✅ Test
• 🤖 Build or CI
• ❓ Other (please specify)

Related

#1903 as the PR where this issue was discussed

Describe this PR

• Didn't get a chance to finish this due to my flight, but hopefully you get the idea here @NSUWAL123
• If I don't get to look at this until Monday, we could go over it together in person 😄
• The context should probably be set just after the OSM login succeeds, then waiting for the redirect will allow the cookie to be set for the subsequent test.
• The context wont save the cookie as it's httpOnly, but should save the OSM login part hopefully, to avoid having to do the Oauth flow for OSM again - let's see!
• In the end the main goal is automated OSM login. To do that we need to make a test OSM account and can just hardcode the creds to this repo. If we optimise by reducing calls to OSM via the auth context, this is a bonus, but not essential for now.

Alternative Approaches Considered

• Disable auth on the backend when DEBUG=true.
• But this would mean we can't test properly with roles, and this could be important in future.

Checklist before requesting a review

• 📖 Read the FMTM Contributing Guide: https://github.com/hotosm/fmtm/blob/main/CONTRIBUTING.md
• 📖 Read the HOT Code of Conduct: https://docs.hotosm.org/code-of-conduct
• 👷‍♀️ Create small PRs. In most cases, this will be possible.
• ✅ Provide tests for your changes.
• 📝 Use descriptive commit messages.
• 📗 Update any related documentation and include any relevant screenshots.

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