fix: changing TRIAL variable to self-service-trial

[kiram15]

Changing the variables from expected plan types for self service from Trial to self-service-trial.

Jira:
ENT-11164

For all changes

• Ensure adequate tests are in place (or reviewed existing tests cover changes)

Only if submitting a visual change

• Ensure to attach screenshots
• Ensure to have UX team confirm screenshots

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 87.11%. Comparing base (c3486ef) to head (44ed4c1).
⚠️ Report is 1 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #1727   +/-   ##
=======================================
  Coverage   87.11%   87.11%           
=======================================
  Files         781      781           
  Lines       17876    17878    +2     
  Branches     3746     3727   -19     
=======================================
+ Hits        15572    15574    +2     
  Misses       2229     2229           
  Partials       75       75           

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.