[Doc] Japanese translation

[DanRoscigno]

Add Japanese support for docs

@EsoragotoSpirit can you please work on the dictionary:

docs/translation/en-to-ja-configs/language_dicts/ja.yaml

I copied the English to Chinese one. The upstream project has Japanese support, and so they have a dictionary already for their terms. It may not be useful to you as they are in a different product space.

There are two translated files in this PR, I believe that they have a mix of Japanese and Chinese in them because I used the Chinese dictionary file. The README is updated with instructions to translate to Japanese. Also note the known issues in the README, I will work on those.

Fixes #issue

What type of PR is this:

• BugFix
• Feature
• Enhancement
• Refactor
• UT
• Doc
• Tool

Does this PR entail a change in behavior?

• Yes, this PR will result in a change in behavior.
• No, this PR will not result in a change in behavior.

If yes, please specify the type of change:

• Interface/UI changes: syntax, type conversion, expression evaluation, display information
• Parameter changes: default values, similar parameters but with different default values
• Policy changes: use new policy to replace old one, functionality automatically enabled
• Feature removed
• Miscellaneous: upgrade & downgrade compatibility, etc.

Checklist:

• I have added test cases for my bug fix or my new feature
• This pr needs user documentation (for new or modified features or behaviors)
  • I have added documentation for my new feature or new function
• This is a backport pr

Bugfix cherry-pick branch check:

• I have checked the version labels which the pr will be auto-backported to the target branch
  • 3.4
  • 3.3
  • 3.2
  • 3.1
  • 3.0

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