1. Create two sites Site1 and Site2 and enable local staging on both
2. Generate a lot of content for Site1, e.g. a few hundred web content articles (see the Note below)
3. Submit a publication of Site1's contents from staging to live
4. While publishing is in progress for Site1, start a publication for Site2 in a different browser window
Expected result: The publication for Site2 starts immediately
Actual result: The publication for Site2 gets in Queued status until Site1's publication completes. The publication should be exclusive only within a single site.
Note: Instead of step 2. you can also catch the publication process of Site1 with a debugger breakpoint somewhere within the method LayoutStagingBackgroundTaskExecutor.execute() in order to reproduce the issue