Merge pull request #9232 from jverdeyen/hotfix/upgrade_docs_typo

doc/update/7.9-to-7.10.md

@@ -106,7 +106,7 @@ only contains a root URL (ex. `https://gitlab.example.com/`)
 ## Things went south? Revert to previous version (7.9)
 
 ### 1. Revert the code to the previous version
-Follow the [upgrade guide from 7.8 to 7.8](7.8-to-7.9.md), except for the database migration
+Follow the [upgrade guide from 7.8 to 7.9](7.8-to-7.9.md), except for the database migration
 (The backup is already migrated to the previous version)
 
 ### 2. Restore from the backup:
@@ -115,4 +115,4 @@ Follow the [upgrade guide from 7.8 to 7.8](7.8-to-7.9.md), except for the databa
 cd /home/git/gitlab
 sudo -u git -H bundle exec rake gitlab:backup:restore RAILS_ENV=production
 ```
-If you have more than one backup *.tar file(s) please add `BACKUP=timestamp_of_backup` to the command above.
\ No newline at end of file
+If you have more than one backup *.tar file(s) please add `BACKUP=timestamp_of_backup` to the command above.