Add user journey test for canceling a build

[peytondmurray]

Fixes #674.

Description

This PR adds a user journey test for canceling a build.

This pull request:

• Adds a new user journey test
• Refactors some of api_utils.py to use a new wait_for_condition function to poll the conda-store-server

Pull request checklist

• Did you test this change locally?
• Did you update the documentation (if required)?
• Did you add/update relevant tests for this change (if required)?

How to test

Run the conda-store server:

docker compose up

Then run the test:

cd conda-store-server
pytest tests/user_journeys/test_user_journeys.py::test_cancel_build

[netlify]

✅ Deploy Preview for conda-store canceled.

Name	Link
🔨 Latest commit	e722f70
🔍 Latest deploy log	https://app.netlify.com/sites/conda-store/deploys/661d9777c6dd0d0008d8f94a

[netlify]

✅ Deploy Preview for conda-store canceled.

Name	Link
🔨 Latest commit	89b3bd8
🔍 Latest deploy log	https://app.netlify.com/sites/conda-store/deploys/661d9783abf1ca0008b6a27f

[dcmcand]

🚀