Remove “to clipboard” from all copy buttons

What does this MR do?

Removes the “to clipboard” part from all “copy to clipboard” buttons, per gitlab-org/gitlab-services/design.gitlab.com!1573 (merged) (depends on this MR).

Screenshots

Will change the following buttons, example:

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation created/updated or follow-up review issue created
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content