[DO NOT MERGE UNTIL KDS v5.0.0-rc3 INSTALLED] Remove hard-coded vuetify color on hover using $darken_ utitlity

[shivam-daksh]

Summary

This PR addresses the issue of replacing the Vuetify color with the Kolibri Design System's (KDS) darken utility. Specifically, it updates the background color for the button that uses the Vuetify --v-error-darken1 color variable.

Changes Made

• Replaced the usage of var(--v-error-darken1) with the corresponding $darken_ utility from the Kolibri Design System once it is provided.
• Updated the button's background color to maintain the appropriate shade when not in the hovered state, ensuring consistency with the KDS design standards.

Testing

• Verified that the button's color remains consistent with the Kolibri Design System's color palette.
• Ensured that the color updates do not affect other components.

Additional Context

This change improves the alignment with the Kolibri Design System and helps maintain design consistency across the application.

Screenshots (if applicable)

Does this introduce any tech-debt items?

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Reviewer guidance

How can a reviewer test these changes?

Are there any risky areas that deserve extra testing?

References

#4634

Comments

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Contributor's Checklist

PR process:

• If this is an important user-facing change, PR or related issue the CHANGELOG label been added to this PR. Note: items with this label will be added to the CHANGELOG at a later time
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Studio-specifc:

• All user-facing strings are translated properly
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Testing:

• Code is clean and well-commented
• Contributor has fully tested the PR manually
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• Critical and brittle code paths are covered by unit tests

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Reviewer's Checklist

This section is for reviewers to fill out.

• Automated test coverage is satisfactory
• PR is fully functional
• PR has been tested for accessibility regressions
• External dependency files were updated if necessary (yarn and pip)
• Documentation is updated
• Contributor is in AUTHORS.md

[MisRob]

Thanks @shivam-daksh! I will invite my colleague @ozer550 to review.

Even though we can complete the review, just leaving a note here that we will merge it after the newest KDS release containing $darken utility is installed into Studio.

[ozer550]

The changes look correct to me! I have tested them out locally and the results are similar.

[MisRob]

Thank you @shivam-daksh and @ozer550. All looks good to me too! We will merge as soon as this KDS release is in Studio (that should also resolve the tests failure).