Fixes scrollbar in time series

What does this MR do?

What does this MR do?

Updates scroll handles to use GitLab's svg icon.

Before	After

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

Related to https://gitlab.com/gitlab-org/gitlab-ce/issues/64385