UHF-12569 List of plans

[khalima]

UHF-12569

What was done

• Separated the RSS feed fetcher to a separate utility function.
• Added a test which tests, that the list of plans items have the same items as the RSS feed.

How to install

• Get the feature branch
  • git fetch && git checkout UHF-12569
• Install the testing tools
  • nvm use && npm i

How to test

•  Make sure your .env has this set: KYMP_BASE_URL="https://helfi-kymp.docker.so"
• Run the tests npx playwright test tests/sites/kymp/listOfPlans.spec.ts and check that they pass.
• Check that the code follows our standards