Update Jetty to 9.4.1.v20170120 in buck build

Update Jetty to 9.4.1.v20170120 in buck build

5e8e2179b218ede7d14b69dc5149b0691b5859cf (Update Jetty to
9.4.1.v201470120, 2017-01-26) updated Jetty in the maven build.
Update the buck build to match so buck builds work again.

The buck build will go away soon, but in the meantime (until the bazel
build gets the same level of support) it is convenient as a faster way
of running tests than using maven.

The bazel build doesn't need this change since it doesn't build or run
http tests yet.

Change-Id: Ibbdaf2880e76b32fc9f6b5605a2ff29e3deffda2