afanasy: delete copy and move operators of af::Msg

[grische]

While debugging, I accidentally used the copy assignment in a test which lead me down completely wrong rabbit hole.
Deleting them explicitely will throw compile errors in case they are being used somewhere.

[timurhai]

We use only those constructors and operators, that a implemented.
Debugging such a complex program is not a good approach.
The best way it to catch a bug.
ps
If there are any errors in such mature classes it should not work at all.
And it works in many companies 24/7.
You just faced some job that cause special bug.

[grische]

This has nothing to do with any bug, it's just code improvements that make it easier to work on the cgru code.