[Java] [Microprofile] Remove unused CXF dependency

[zUniQueX]

Follow-up for #6680.
Using the microprofile library requires an additional (unnecessary) dependency in a project. If one uses a different implementation than CXF, e.g. Jersey, the CXF dependency has to be pulled in additionally. But Jersey has an own implementation for multipart handling.

The dependency and the corresponding import aren't used at the moment. Thus, they can be safely deleted.

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[wing328]

thanks for the PR. let's give it a try

[miguelborges99]

The PR #15364 has broken master branch

[wing328]

@miguelborges99 noticed that too. reverted the change via #15392