ci,java: allow different build types

We do not need to specify the CMAKE_BUILD_TYPE: Release as an env variable since we already default to release, as shown here: https://gitlab.kitware.com/vtk/vtk/-/blob/master/.gitlab/ci/configure_common.cmake?ref_type=heads#L43

We need this change since we need to be able to change the build type using an ENV variable in the gitlab UI for scheduled jobs.

Backport: release:HEAD~2