Introduce :launchpad/jvm-opts

[arichiardi]

Make sure we populate the internal :java-args from the above-mentioned key, therefore allowing deps.local.edn to contain things that differ from deps.edn.

Note that there is naming discrepancy as this patch sticks with the official key - :jvm-opts rather than the internal name.

The behavior of appending to existing :jvm-opts, in order, has been preserved as per the tools.deps built-in.