The Replay action gets stuck upon finding a conflict on a page, regardless of whether an answer is stored for that page or not

Steps to reproduce

1. Login as Admin
2. Create 2 subwikis (subwiki1 and subwiki2)
3. Install an older version of an application in those subwikis (e.g. Blog App 9.13.1)
4. Go to one of subwikis (e.g. subwiki1) and modify a page on the respective application (for ex. on Blog App go to Blog.RssCode and empty it)
5. On the same subwiki (e.g. subwiki1) go to Administer Wiki > Extensions > Extensions
6. Search for the previously installed app (e.g. Blog)
7. Click 'Upgrade' > 'Continue'
8. When the page merge conflict is displayed (e.g. for modified page Blog.RssCode), select 'Keep the new version of the page'
9. Click 'Continue'
10. On the same subwiki (e.g. subwiki1) go to Administer Wiki > Extensions > History
11. Select the Blog App upgrade action (e.g. "Blog Application 9.13.2")
12. Click 'Export' and save the .XML file
13. Go to the other subwiki (e.g. subwiki2) and modify a page as well on the application (for ex. on Blog App go to Blog.BlogCode and empty it)
14. Go to Main Wiki > Administer Wiki > Extensions > History
15. Import the previously saved .XML file at Step 12
16. Check the box for the upgrade action
17. Click 'Replay' button
18. Fill the name of the subwiki not yet upgraded (e.g. subwiki2)
19. Click 'Continue' > 'Start' buttons

Expected results

• The replay of the application upgrade is finished successfully on the other subwiki (e.g. subwiki2).
• A question is asked to the user by the replay action for question Blog.BlogCode for subwiki2.

Actual results

The upgrade process is stuck (an endless spinning wheel displayed) at line:

Conflict between [@@ -1,1209 +1,0 @@] and [@@ -1,1209 +1,1209 @@]

The issue was reproduced initially by lucaa.