build(deps): bump darling from 0.21.1 to 0.21.3

[dependabot]

Bumps darling from 0.21.1 to 0.21.3.

Release notes

Sourced from darling's releases.

v0.21.3

• Fix: Forward Override::<T>::from_expr to T::from_expr #371

v0.21.2

• Add #[darling(from_expr = ...)] when deriving FromMeta to support overriding the key-value form #369
• Keep parsing the body and type params even if there are errors from parsing attributes. #7
• Support #[darling(with = ...)] on the generics field when deriving FromDeriveInput.
• Return an error, rather than panicking, when doing shape validation on a union. #365

Changelog

Sourced from darling's changelog.

v0.21.3 (August 22, 2025)

• Fix: Forward Override::<T>::from_expr to T::from_expr #371

v0.21.2 (August 14, 2025)

• Add #[darling(from_expr = ...)] when deriving FromMeta to support overriding the key-value form #369
• Keep parsing the body and type params even if there are errors from parsing attributes. #7
• Support #[darling(with = ...)] on the generics field when deriving FromDeriveInput.
• Return an error, rather than panicking, when doing shape validation on a union. #365

Commits

• f21aa2c Bump version to 0.21.3
• 84f6fba Directly forward non-paths in Override
• 138c450 Override Override::from_expr (#372)
• 65d73d1 Bump version to 0.21.2
• 3e65b82 Update changelog
• f9c8222 Expose from_expr option when deriving FromMeta (#370)
• 59a46eb Don't panic if shape validation is used with a union
• f5b7aef Change rust-version to make lock file versioning work
• 90a3132 Fix clippy violation
• 50a814d Enable #[darling(with = ...)] for generics field
• Additional commits viewable in compare view

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[github-actions]

I'm approving this pull request because it only includes patch or minor updates.