Closes #6349: Update renewal banner with discount percentage instead of difference

[jeawhanlee]

Description

This PR Updates the Renewal banner with discount percentage.

Fixes #6349

Type of change

• Enhancement (non-breaking change which improves an existing functionality).

Is the solution different from the one proposed during the grooming?

No

Checklists

Generic development checklist

• My code follows the style guidelines of this project, with adapted comments and without new warnings.
• I have added unit and integration tests that prove my fix is effective or that my feature works.
• The CI passes locally with my changes (including unit tests, integration tests, linter).

Test summary

• I triggered all changed lines of code at least once without new errors/warnings/notices.
• I validated all Acceptance Criteria of the related issues. (If applicable, provide proof).
• I validated all test plan the QA Review asked me to.

[Mai-Saad]

working as expected with the following note (agreed to be ok)

• when 4 days < Expired <=15 days, auto-renew off, not white label and optimization on => bubble is there ( same on the trunk) Referring to https://docs.google.com/spreadsheets/d/1Zu1MbsVNkOWCsW0CmVRuY69I0t3vtTLG4ykhuOI3YVI/edit#gid=418280516
• % change will apply on expiring soon
• with FR translation (expiring soon), the final price isn't bold (same on trunk)