Suspend the active SparkSession in case "function" creates new threads that can end up inheriting it.
Suspend the active SparkSession in case "function" creates new threads that can end up inheriting it. Currently used during hive client creation otherwise the BoneCP background threads hold on to old sessions (even after a restart) due to the InheritableThreadLocal. Shows up as leaks in unit tests where lead JVM size keeps on increasing with new tests.