Fix Publish EPUB tests that are failing on Linux
Fix Publish EPUB tests that are failing on Linux

The changes were caused by the fix for BL-6760, and these changes should
have been part of that fix.

StephenMcConnel/BloomDesktop,StephenMcConnel/BloomDesktop,StephenMcConnel/BloomDesktop,gmartin7/myBloomFork,BloomBooks/BloomDesktop,BloomBooks/BloomDesktop,gmartin7/myBloomFork,StephenMcConnel/BloomDesktop,gmartin7/myBloomFork,gmartin7/myBloomFork,BloomBooks/BloomDesktop,StephenMcConnel/BloomDesktop,gmartin7/myBloomFork,StephenMcConnel/BloomDesktop,BloomBooks/BloomDesktop,BloomBooks/BloomDesktop,BloomBooks/BloomDesktop,gmartin7/myBloomFork