Merge branch '439704-fix-admin-usage-trends-chart' into 'master'

Fixed empty tooltips in usage trends count charts

See merge request https://gitlab.com/gitlab-org/gitlab/-/merge_requests/159906



Merged-by: Ezekiel Kigbo <3397881-ekigbo@users.noreply.gitlab.com>
Approved-by: Alex Pennells <apennells@gitlab.com>
Approved-by: Ezekiel Kigbo <3397881-ekigbo@users.noreply.gitlab.com>
Reviewed-by: Ezekiel Kigbo <3397881-ekigbo@users.noreply.gitlab.com>
Reviewed-by: Alex Pennells <apennells@gitlab.com>
Reviewed-by: Rudy Crespo <rcrespo@gitlab.com>
Co-authored-by: Rudy Crespo <rcrespo@gitlab.com>