Java 14 Support?

[gary-archer]

Nice library guys - have been using it for a while - makes non blocking Rest API code much easier to write reliably.

Just wondered if it could be updated to support the latest Java, which I was trying to use?
I believe the below issue is related to the version of ASM dependencies.

Not massively urgent, but nice to keep your library working with latest versions.

Caused by: java.lang.IllegalArgumentException: Unsupported class file major version 58
at com.ea.async.shaded.org.objectweb.asm.ClassReader.(ClassReader.java:195)
at com.ea.async.shaded.org.objectweb.asm.ClassReader.(ClassReader.java:176)
at com.ea.async.shaded.org.objectweb.asm.ClassReader.(ClassReader.java:162)
at com.ea.async.instrumentation.Transformer.transform(Transformer.java:150)

[Mart-Bogdan]

Looks like it could be tended with this PR #51