[java/*] Updated Java links & fixed formatting

[ThunderE75]

• I solemnly swear that this is all original content of which I am the original author
• Pull request title is prepended with [language/lang-code] (example [python/fr-fr] or [java/en])
• Pull request touches only one file (or a set of logically related files with similar changes made)
• Content changes are aimed at intermediate to experienced programmers (this is a poor format for explaining fundamental programming concepts)
• If you've changed any part of the YAML Frontmatter, make sure it is formatted according to CONTRIBUTING.md
  • Yes, I have double-checked quotes and field names!

[ThunderE75]

I had a question regarding updating links on the translated pages,

1. In the de-de variant of this file, it already has the same outdated book links, but the books are in English, is this okay to have book resources of other language ?
2. & in the case of the es-es variant of this file, it doesn't have links to those book resources, should we add English book links as resources, or leave it as is ?

Another doubt i have is, Should i open a PR for each translated file separately, or is it okay to have 'similar' updates of different translation under the same PR ? I have read the Contributing guidelines, but it's a confusing for me, so i am just confirming, before adding more commits to this PR.

[verhovsky]

is this okay to have book resources of other language

yes, why wouldn't it be?

es-es variant of this file, it doesn't have links to those book resources, should we add English book links as resources, or leave it as is

whatever you want

Should i open a PR for each translated file separately

why would you want to write the same commit message 13 times?

I have read the Contributing guidelines

just use your judgement, it's not that serious.

[ThunderE75]

• Fixed Formatting to match the main en version
• Added Missing resource links

• Though, i am not native/flute in most of these language, but i believe that i have translated & checked my commits multiple times to insure that there are no grammatical mistakes
• I have also not added additional English books to those pages that didn't have them previously, but i have updated the links on the pages that had them already.