Replace feed cypress test with equivalent pytest

[brianpeiris]

Detailed information:

• Deleted feed.cy.js and replaced it with an equivalent pytest in app/feed/tests/test_feed_routes.py
• Removed obsolete feedEndpoint cypress command.

Closing issues:

List all issues the pull request solve:

• Closes #394

Test plan (required)

• [x] The PR contains new PyTest unit/integration tests for any function or functional added.
• [x] The PR changes existing PyTest unit/integration tests to keep all tests up to date.
• [x] The PR does not lead to degradation in unit test coverage.
• [x] Project parts affected by changes in this PR was tested manually on your local (using Postman or in any other way). List everything you've tested below:
  • ran all pytests

[codecov-commenter]

Codecov Report

Base: 66.71% // Head: 66.71% // No change to project coverage :thumbsup:

Coverage data is based on head (3c46140) compared to base (ee6427e). Patch has no changes to coverable lines.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## develop #464 +/- ## ======================================== Coverage 66.71% 66.71% ======================================== Files 81 81 Lines 2569 2569 Branches 313 313 ======================================== Hits 1714 1714 Misses 828 828 Partials 27 27 ``` | [Impacted Files](https://codecov.io/gh/ClimateMind/climatemind-backend/pull/464?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=ClimateMind) | Coverage Δ | | |---|---|---| | [conftest.py](https://codecov.io/gh/ClimateMind/climatemind-backend/pull/464/diff?src=pr&el=tree&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=ClimateMind#diff-Y29uZnRlc3QucHk=) | `100.00% <ø> (ø)` | | Help us with your feedback. Take ten seconds to tell us [how you rate us](https://about.codecov.io/nps?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=ClimateMind). Have a feature suggestion? [Share it here.](https://app.codecov.io/gh/feedback/?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=ClimateMind)

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