Update build config to include examples dir

Explicitly include `examples` dir in sdist.

The same would be achieved, by removing explicit includes, which
currently would also add these files/dirs:

```
/gitattributes
/github
/mypy_cache
/readthedocs.yaml
/verify_release
```

Maybe we should instead of defining includes, explicitly exclude
(some of) these files? The advantage of a blacklist approach is
that it becomes less likely to forget including files that should
be in included.

See hatch docs for:
- what files should be in sdist
https://ofek.dev/hatch/latest/plugins/builder/#source-distribution

- what files get into sdist by default:
https://ofek.dev/hatch/latest/plugins/builder/#default-file-selection_1

- how to configure what files get into sdist:
https://ofek.dev/hatch/latest/config/build/#file-selection

Fixes #1901

Signed-off-by: Lukas Puehringer <lukas.puehringer@nyu.edu>

Author: Lukas Puehringer

pyproject.toml

@@ -59,6 +59,7 @@ path = "tuf/__init__.py"
 [tool.hatch.build.targets.sdist]
 include = [
   "/docs",
+  "/examples",
   "/tests",
   "/tuf",
   "/requirements*.txt",