Weblate: Improper access control for pending tasks in API
### Impact
The API for tasks didn't verify user access for pending tasks. This could expose logs of in-progress operations to users who don't have access to given scope.
### Patches
*
https://github.com/WeblateOrg/weblate/pull/18515
### Workarounds
The attacker needs to guess the random UUID of the task, so exploiting this is unlikely with the default API rate limits.
### References
This issue was identified by Michal Čihař.