Make bert_japanese and cpm independent of their inherited modules
Author: Davidy22
Pull request: yes

# What does this PR do?
Another step towards completion of #19303

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Comments:
_The documentation is not available anymore as the PR was closed or merged._

Not going to let some hash collision stop me from publishing something that passes everything else.

Of note, I actually removed a test from the japanese test suite that appeared to be checking to make sure that it was inheriting from the module that this pr is decoupling the japanese bert from. Implication I suspect being that the original author especially cared that this relation would be in place and enforced.

Well, changing the import source did the job, the quick skim and assumption I made from the error wasn't quite on the mark

Thanks again for your contribution!

Probably going to scour the warnings as mentioned last time next, having some trouble with locally running tests but ci probably has my back