XWIKI-10151: Collapse the extension job log when there is a merge conflict

(cherry picked from commit 0e8d49f791bb4ecb16c8e6d7281a51a223118671)
XWIKI-9199: Possibility to automatically overwrite pages which have a merge conflict when upgrading using DW

(cherry picked from commit 057867ea4483be0f8507daa68a2571cdc3f6d900)