Remove gl-button from star button

What does this MR do?

This MR fixes a regression introduced by a mass insertion of gl-button classes !45005 (merged).

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Does this MR meet the acceptance criteria?

Conformity

• [ ] Changelog entry Not needed since this fixes an issue introduced in the same milestone.
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content