Bump setuptools to 78.1.1 (backport #1069)

[mergify]

Bumps setuptools from 75.8.2 to 78.1.1.

Changelog

Sourced from setuptools's changelog.

v78.1.1

Bugfixes

• More fully sanitized the filename in PackageIndex._download. (#4946)

v78.1.0

Features

• Restore access to _get_vc_env with a warning. (#4874)

v78.0.2

Bugfixes

• Postponed removals of deprecated dash-separated and uppercase fields in setup.cfg. All packages with deprecated configurations are advised to move before 2026. (#4911)

v78.0.1

Misc

• #4909

v78.0.0

Bugfixes

• Reverted distutils changes that broke the monkey patching of command classes. (#4902)

Deprecations and Removals

• Setuptools no longer accepts options containing uppercase or dash characters in setup.cfg.

... (truncated)

Commits

• 8e4868a Bump version: 78.1.0 → 78.1.1
• 100e9a6 Merge pull request #4951
• 8faf1d7 Add news fragment.
• 2ca4a9f Rely on re.sub to perform the decision in one expression.
• e409e80 Extract _sanitize method for sanitizing the filename.
• 250a6d1 Add a check to ensure the name resolves relative to the tmpdir.
• d8390fe Extract _resolve_download_filename with test.
• 4e1e893 Merge https://github.com/jaraco/skeleton
• 3a3144f Fix typo: pyproject.license -> project.license (#4931)
• d751068 Fix typo: pyproject.license -> project.license
• Additional commits viewable in compare view

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This is an automatic backport of pull request #1069 done by [Mergify](https://mergify.com).

[mergify]

Cherry-pick of 52ce7fa has failed:

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