Disable nailgun by default

[jgranstrom]

Nailgun is likely causing more harm than good, and it is likely safest to flip the default for it. Is is also deprecated and unmaintained at this point.

There's been some prior discussions:

• Turn nailgun initialization message down to debug #21865
• JVM: Pants/Nailgun and future JDKs releases (after version 17) #20603 (does not build JVM after 17)
• Nailgun may break hermeticity for scala compilations #21146 (may not be hermetic)
• There's also some scheduler initialization overhead that may be unnecessary

I created a PR for it so that it doesn't get lost