fix: prioritize the redemption over request

[ahmad-hassan-dev]

Description

Previously, the enrollment logic was hiding the "Enroll" button if a learner was eligible to request a subsidy, even when they also had a direct, redeemable subsidy (like a course assignment) available. This prevented learners from immediately enrolling in courses they already had access to.

This change adjusts the priority of the enrollment actions. The logic now checks for any applicable, redeemable subsidy before it checks for the ability to request one.

As a result, if a learner has any subsidy that allows for direct enrollment, the "Enroll" button will now be correctly displayed, taking precedence over the "Request" flow.

For all changes

• Ensure adequate tests are in place (or reviewed existing tests cover changes)
• Ensure English strings are marked for translation. See documentation for more details.

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 90.35%. Comparing base (9b33e37) to head (3b3ec33).
Report is 2 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff           @@
##           master    #1398   +/-   ##
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  Coverage   90.35%   90.35%           
=======================================
  Files         419      419           
  Lines        9475     9475           
  Branches     2210     2210           
=======================================
  Hits         8561     8561           
  Misses        880      880           
  Partials       34       34           

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[sameenfatima78]

Just one concern over giving priority to redemption over request, we need to verify what happens in case of Subscriptions B&R?

[sameenfatima78]

Also, what if we simply add this additional condition to the existing code:

Original:

if (userCanRequestSubsidyForCourse) {
    // User can request a subsidy for the course, but is not enrolled so
    // hide the "Enroll" CTA in favor of the "Request enrollment" CTA below
    // the course run cards.
    return null;
  }

Proposed:

if (userCanRequestSubsidyForCourse && !userSubsidyApplicableToCourse) {
    // User can request a subsidy for the course, and no existing subsidy is applicable to the course so
    // hide the "Enroll" CTA in favor of the "Request enrollment" CTA below
    // the course run cards.
    return null;
  }