Remove unused default heap size from distribution expansion variables (#68186)
Remove unused default heap size from distribution expansion variables (#68186)

The default heap size now resides in MachineDependentHeap and is applied
per our auto heap settings logic there vs living in jvm.options. For
this reason we no longer need to fill this in at build time, so we can
ditch these template variables.
GlenRSmith/elasticsearch,robin13/elasticsearch,GlenRSmith/elasticsearch,GlenRSmith/elasticsearch,robin13/elasticsearch,GlenRSmith/elasticsearch,robin13/elasticsearch,robin13/elasticsearch,GlenRSmith/elasticsearch,robin13/elasticsearch