Enable Netty 4 advanced leak detection in tests and fail the build if there is a leak

[jasontedor]

Netty has pooled and unpooled byte buf alloactors. The pooled allocator uses reference counting to track when a byte buf can be returned to the pool, and leak detection to ensure that byte bufs are properly accessed/released. Netty has different levels of detection from disabled to paranoid (check every access). We should enable leak detection in tests and fail the build if a leak is detected.

Relates #19526, relates #19562

[original-brownbear]

Gave this a go in #31861 :)