fix(charts): fix toolbox icons default + hover colors

mentioned in commit af5832b0

mentioned in merge request gitlab-org/frontend/pajamas-adoption-scanner!95 (merged)

mentioned in merge request status-page!650 (merged)

mentioned in merge request gitlab-docs!3313 (merged)

mentioned in merge request gitlab!104759 (merged)

mentioned in merge request gitlab-org/frontend/pajamas-adoption-scanner!104 (merged)

mentioned in merge request status-page!653 (merged)

mentioned in merge request gitlab!105756 (merged)

mentioned in merge request gitlab-docs!3335 (merged)

mentioned in merge request gitlab-org/gitlab-services/design.gitlab.com!3172 (merged)

mentioned in merge request gitlab-org/gitlab-services/design.gitlab.com!3173 (merged)