feat(echarts): update to echarts@5.6.0

mentioned in commit f8c6c617

mentioned in merge request gitlab-svgs!1176 (merged)

mentioned in merge request status-page!903

mentioned in merge request gitlab-org/gitlab-services/design.gitlab.com!4482 (merged)

mentioned in merge request gitlab-org/technical-writing/docs-gitlab-com!741 (merged)

mentioned in merge request gitlab-org/editor-extensions/gitlab-jetbrains-plugin!1731 (merged)