Fix variable name in Java build script (#9161)

Fixes an incorrect variable reference in java/ci/build-in-docker.sh for configuring whether C++ tests should be built.

Authors:
  - Jason Lowe (https://github.com/jlowe)

Approvers:
  - Robert (Bobby) Evans (https://github.com/revans2)

URL: #9161

java/ci/build-in-docker.sh

@@ -52,7 +52,7 @@ export LIBCUDF_KERNEL_CACHE_PATH=/rapids
 rm -rf "$WORKSPACE/cpp/build"
 mkdir -p "$WORKSPACE/cpp/build"
 cd "$WORKSPACE/cpp/build"
-cmake .. -DUSE_NVTX=$ENABLE_NVTX -DCUDF_USE_ARROW_STATIC=ON -DCUDF_ENABLE_ARROW_S3=OFF -DBUILD_TESTS=$SKIP_CPP_TESTS -DPER_THREAD_DEFAULT_STREAM=$ENABLE_PTDS -DRMM_LOGGING_LEVEL=$RMM_LOGGING_LEVEL
+cmake .. -DUSE_NVTX=$ENABLE_NVTX -DCUDF_USE_ARROW_STATIC=ON -DCUDF_ENABLE_ARROW_S3=OFF -DBUILD_TESTS=$BUILD_CPP_TESTS -DPER_THREAD_DEFAULT_STREAM=$ENABLE_PTDS -DRMM_LOGGING_LEVEL=$RMM_LOGGING_LEVEL
 
 make -j$PARALLEL_LEVEL
 make install DESTDIR=$INSTALL_PREFIX