Remove -Xmx Java args to allow Java to scale memory to container limit

[birkland]

See description in: https://www.atamanroman.dev/articles/usecontainersupport-to-the-rescue/

Essentially, as long as -Xmx is not defined Java will automatically use 1/4 the container memory limit for the heap size. Since isle-buildkit does define -Xmx, we need to remove it, in order to allow the JVM to auto-size.

Resource limits are introduced in idcApp-k8s as of jhu-idc/idcApp-k8s#57

[htpvu]

I have no idea where this work should be done. THis ticket does not look like it should block the feature completion launch from the DRCC team. But a review of this by a developer post launch would probably be a good idea.