Fix some links and typos in examples

[adeak]

I came across some minor mistakes while browsing some examples.

Some notes:

1. In the Marching Cubes example the text said "flying edges" but the code said marching_cubes for the latter part of the example. Since flying edges works too, I changed to code accordingly.
2. In my local build of the 2D streamlines example the first block of code with the sphinx gallery comment is somehow empty. Don't know why. I wonder if we should merge that line of code with the subsequent imports, but then the text would read a bit clumsier, so we might also have to rephrase that a bit.
3. In the online docs the Types of Shading example has blank black figures at the end (looks fine in the released docs.pyvista.org version). I wonder if this is somehow related to antialiasing. In any case my local build works fine for these figures.
4. I've expanded the main makefile so that codespell ignores .vtu files. Otherwise my pre-commit hook mentioned in Add return_closest_point as optional parameter for find_closest_cell #2029 (comment) would block committing.

[adeak]

"Build and push Docker image" step fails with

Error: buildx failed with: error: denied: installation not allowed to Write organization package

I wonder if this is due to the non-pyvista branch, or due to my user's lack of privileges. In comparison the also-recent #2029 didn't fail with this. This is something that needs to be looked at, because regular contributors will also trip it unless it's just some fluke (cc. @akaszynski).

[codecov]

Codecov Report

Merging #2030 (556541e) into main (49d16f1) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main    #2030   +/-   ##
=======================================
  Coverage   93.06%   93.06%           
=======================================
  Files          74       74           
  Lines       15531    15531           
=======================================
  Hits        14454    14454           
  Misses       1077     1077           

[akaszynski]

I think it's auth issues. We may disable this for now. Pinging @banesullivan

[akaszynski]

@banesullivan, I'm only building on tags. Is this fine?

[akaszynski]

LGTM. We'll push only on tag for now to not block external contributors.

[banesullivan]

I'll look into the Docker build auth issues. I think I know what's going on there