it means your next upgrade is 10.8.7. Basically all the versions between 9.5.x and 10.8 weren’t deemed as important steps to go through until you get to 10.8.7. Maybe because there weren’t any migrations or major changes that 9.5 didn’t already address.
Then continue with the next version on the upgrade path as per the Gitlab docs. Make sure to wait for background migrations to finish before starting the next upgrade. The docs cover it.