merge networkx Graph classes from python-type-stubs and address a few recent issues

[Avasam]

Extracted from #14038 with a few additional changes. Should reduce changes in that PR

Changes:

• Removed int from degree-related returns (fixes networkx: Types for Graph properties are more general than required #14592 )

  • Note: This should be fully compatible with @charmoniumQ 's changes in Correct type annotations on NetworkX DiGraphs #14595

• Added back Liskov's Substitution Principle considerations from before complete networkx/digraph.pyi addresses #14499 follows #14509 #14569 and Complete networkx/graph.pyi. #14499 #14509

  • See networkx: Types for Graph properties are more general than required #14592 (comment)
  • I also slightly changed the wording of my comments to make them more obvious they relate to LSP

• Moved comments above their related location, rather than under (pretty sure we have an unwritten convention of placing comments on the same line or above)

• Removed redundant comments that just spell the annotated return type

• Ordered functions to consistently match runtime

• Graphs were inconsistently (as in it was only done sometime) overriding Graph methods with the same signature as their parents. I went with the following consistent approach (I'm fine switching to always overriding methods if present on the specific subclass at runtime, as long as we're consistent here)

  NOTE: Graph subclasses relationships are so complex we're only overriding methods that differ in signature from the base classes to use inheritance to our advantage and reduce complexity

  Edit: From @Akuli : What tools and process should I use? #14499 (comment)

  • You have included various things that are inherited from the base class Graph. In typeshed, we like to repeat things inherited from a base class only if we want something different than the definition in base class (such as the to_undirected method).

  So we seem to be on the same track here.

There seems to have been a bit on confusion regarding these stubs recently, let's take the time to properly review these changes, and discuss any uncertainty (whilst I do think this PR is correct, I could be wrong)

CC @srittau @TomerGodinger

[Avasam]

This isn't strictly necessary and I don't mind removing it from the PR if unwanted

[Avasam]

Extracted reportviews.pyi changes to #14732

[github-actions]

According to mypy_primer, this change has no effect on the checked open source code. 🤖🎉