Upgrade to latest EPUBCheck v. 5.1.x

[karenhanson]

EPUB 3.3 is now released along with an updated EPUBCheck v.5.1.x. Both are backward compatible with prior versions. The EPUB module needs to be updated to support the latest version. More info here: https://www.w3.org/2023/05/pressrelease-epub33-rec.html.en

Note: I plan to work on this when I have a chance, so please feel free to assign this to me! :)

[karenhanson]

I started this change on my branch: https://github.com/karenhanson/jhove/tree/update-to-epub-5-0-1
I had to make some changes to get the tests working. The biggest concern I have is that FontFile boolean might not be reporting accurate information. Assuming I'm understanding its purpose correctly, it appears to always be false regardless of whether the font file is embedded. I've logged an issue with EPUBCheck. You can see notes about this and other changes on this commit comment: f360f8c
I'll come back to this in a few months and decide what to do about FontFile based on whether there is a response to the issue I logged.

[karenhanson]

Update: EPUBCheck released 5.1.0, which fixed the font issue and reverted a change that was causing resources not to be listed. I have therefore jumped to 5.1.0:
karenhanson@412e4ab
This is almost ready for a PR, except I noticed that the report no longer includes Creation Date so I logged an issue to see if it was likely to be added back in. Turns out they will add it in to the next maintenance release (presumably 5.1.1). I don't think this will take too long, so I'll watch for that release. Once it's out I'll wrap this up and do a PR.