[FUI05] Remove wimax data usage unit test

In follow-up patches, the network type will be derived from
transport types, which officially doesn't support wimax.
Thus, remove the test which rely on it first since it is
not needed and will not be needed.

Test: atest FrameworksNetTests
Bug: 174123988
Change-Id: I713bc2ec39e3a4fa19ed13d2e9ff9ae35477d726