Bump zipp from 3.1.0 to 3.19.1 in /backend

[dependabot[bot]]

Bumps zipp from 3.1.0 to 3.19.1.

Changelog

Sourced from zipp's changelog.

v3.19.1

Bugfixes

• Improved handling of malformed zip files. (#119)

v3.19.0

Features

• Implement is_symlink. (#117)

v3.18.2

No significant changes.

v3.18.1

No significant changes.

v3.18.0

Features

• Bypass ZipFile.namelist in glob for better performance. (#106)
• Refactored glob functionality to support a more generalized solution with support for platform-specific path separators. (#108)

Bugfixes

• Add special accounting for pypy when computing the stack level for text encoding warnings. (#114)

v3.17.0

Features

... (truncated)

Commits

• 6d1cb72 Finalize
• fd604bd Merge pull request #120 from jaraco/bugfix/119-malformed-paths
• c18417e Add news fragment.
• 58115d2 Employ SanitizedNames in CompleteDirs. Fixes broken test.
• 564fcc1 Add SanitizedNames mixin.
• 79a309f Add some assertions about malformed paths.
• 2d015c2 Merge https://github.com/jaraco/skeleton
• a595a0f Rename extras to align with core metadata spec.
• 608f90a Finalize
• 3a22d72 Merge pull request #118 from jaraco/feature/is-symlink
• Additional commits viewable in compare view

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