Update jetty to 9.4.27.v20200227
Update jetty to 9.4.27.v20200227

Many bug fixes in 9.4.25 - 9.4.27, see release notes

https://github.com/eclipse/jetty.project/releases/tag/jetty-9.4.25.v20191220
https://github.com/eclipse/jetty.project/releases/tag/jetty-9.4.26.v20200117
https://github.com/eclipse/jetty.project/releases/tag/jetty-9.4.27.v20200227

Change-Id: Ia8e31cfefa02f397a8eb80f8b417f68d69e2dcc0

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