Add slots to DependencyGraph
Pinned networkx to 3.1
Pinned networkx to latest version supported on python 3.8 to support running salt-ssh to systems with python 3.8
Fixed assignment of env in support helpers VirtualEnv
Restrict networkx version with contraints instead of in base
Fixed setting context retcode in some places where errors are returned.
Removed unnecessary pylint ignore comment.
Reverted importlib-metadata version bump.
Added networkx to versions report
Actually fixed VirtualEnv env assignment from kwargs
