Fix HTML-escaped token and authorization URLs in Java libraries

[JochenReinhardt]

Use triple curly braces to avoid URLs getting HTML-escaped in Java Code.

Fixed Java code generation, so this might be interesting for you: @bbdouglas (2017/07) @sreeshas (2017/08) @jfiala (2017/08) @lukoyanov (2017/09) @cbornet (2017/09) @jeff9finger (2018/01) @karismann (2019/03) @Zomzog (2019/04) @lwlee2608 (2019/10)

To fix #12656

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