Consider programmatically exposing current Netty version

Sometimes Netty makes behavioral/functional changes between minor releases. For example, a recent PR, https://github.com/netty/netty/pull/9442, fixed a race condition with the HTTP/2 codecs. While this is a backwards compatible change from an API perspective, usage of these codecs could yield different results with different versions of Netty.

Visibility on the current Netty version could be beneficial from this perspective alone, esp. for logging purposes… but in the scenario where you might be vending a library that depends on a non-shaded version of Netty, it might be critically important what version of Netty is available on the class path. If the current version was programmatically exposed, libraries could use it to make decisions in a similar fashion that Netty itself uses PlatformDependent.javaVersion().

[jakub-dzon]

@Bennett-Lynch It seems that io.netty.util.Version should do the trick.

[normanmaurer]

@jakub-dzon you are completely right! I honestly did completely forget we already have something like this 🤦‍♂ .

@Bennett-Lynch I will close the ticket now 😃