Correctly resolve overloaded Java methods in hyperlinking

The Scala selection engine didn't build the correct signature
for Java methods taking array parameters. It turns out that
the special-handling `mapParamType` wasn't needed, and the
existing `mapType` method in `ScalaJavaMapper` was already
working correctly.

The test is @Ignored because of [SI-7548](https://issues.scala-lang.org/browse/SI-7548).

Fixed #1000421