Drop confusing second * from glob pattern example

[ntBre]

Summary

As @AlexWaygood noted on the 0.12 release blog post draft, the existing example is a bit confusing. Either **/*.py or just *.py, as I went with here, makes more sense, although the old version (scripts/**.py) also worked when I tested it. However, this probably shouldn't be relied upon since the globset docs say:

Using ** anywhere else is illegal

where "anywhere else" comes after the listing of the three valid positions:

1. At the start of a pattern (**/)
2. At the end of a pattern (/**)
3. Or directly between two slashes (/**/)

I think the current version is luckily treated the same as a single *, and the default globbing settings allow it to match subdirectories such that the new example pattern will apply to the whole scripts tree in a project like this:

.
├── README.md
├── pyproject.toml
├── scripts
│   ├── matching.py
│   └── sub
│       └── nested.py
└── src
    └── main.py

Test Plan

Local testing of the new pattern, but the specifics of the pattern aren't as important as having a more intuitive-looking/correct example.

[github-actions]

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