Update Apache MINA to 3.x

[davido]

Description

Upgrade the project dependency on Apache MINA to version 3.x.

Motivation

In Apache MINA 3.0, the SSH transport protocol was moved into a filter chain, and a client-side proxy implementation was introduced (see apache/mina-sshd#729).

Because of these changes, much of the proxy-related code currently maintained in JGit may no longer be necessary.

In particular, it should be possible to remove most of the files in:

org.eclipse.jgit.ssh.apache/src/org/eclipse/jgit/internal/transport/sshd/proxy

This upgrade would simplify the codebase by relying on the built-in proxy support provided by Apache MINA 3.x.

Alternatives considered

No response

Additional context

No response

[tomaswolf]

@davido: I have done that in a local branch on my machine. (Running the JGit tests with the new 3.0.0-M2 was part of my release tests for Apache MINA SSHD.) But note that Apache MINA SSHD 3.x currently only publishes milestone releases (3.0.0-M2 being the latest; I plan to have an -M3 in the next few weeks).

And yes, once one does that, much of the proxy code in JGit can be removed. After all, I moved exactly that code upstream.

I would prefer to wait with doing this upgrade in JGit until we have a final 3.0.0 release upstream.

[merks]

I stumbled upon this. Indeed would hope to consume only released versions not milestone version in Orbit...

https://github.com/eclipse-orbit/orbit-simrel/blob/1d4764ee7fc8e96d1060042222a059de11370c17/maven-osgi/tp/Maven.target#L905-L916

[msohn]

I agree we should not consume a milestone version of a security critical library.
Hence let's wait until 3.0.0 has been released.