Endless spinning wheel still displayed in progress logs when a subwiki creation is finished can be confusing

Steps to reproduce

1. Go to Drawer > Wiki Index
2. Click 'Create Wiki' button
3. Type a Pretty Name, a Wiki Identifier and select the Flavor
4. Click 'Next Step' button
5. Click 'Create' button
6. After the subwiki creation process is finished, observe the logs in the browser page

Expected results

After the subwiki creation is finished, no spinning wheel is displayed in the logs.

Actual results

Even if the subwiki creation process is finished, the endless spinning wheel is still displayed in the logs on the beginning of the last line:

Finished job of type [wikicreationjob] with identifier [wikicreation/createandinstall/<subwiki>]

which can be confusing for users, since the spinning wheel usually indicates that something is still in progress.

The longer #printLogs take, the likelier it is that a race condition occurs (i.e., the status of the job pass to FINISHED during the execution of #printLogs).
Meaning that, the issue was existing since XWIKI-10043, but is getting easier to experience as the number of operations required to initialize a sub-wiki grows.