[resotocore] allow creation of custom edges

[lloesche]

Motivation

Right now all edges are defined by the collector plugins. Users might want to create custom edges that allow to correlate data between different collectors. A very obvious example would be correlating a tag on a cloud resource containing a resource owners email address to that email address in something like Google Workspace or Okta, Onelogin, etc.

Desired Behavior

Introduce an API and CLI command that allows to create edges based on matching attributes between nodes.

Syntax could look something like this:

query is(aws_resource) and tags.owner != null | connect <-[owner]- query is(slack_user) and email = {tags.owner}

Additional Context

No response