[Java][webclient] fix missing dependencies in build.gradle

[wing328]

• fix missing dependencies in build.gradle
• update jersey1 junit to a newer version

For #5690 (comment)

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cc @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) @bkabrda (2020/01)