[ci] Roll pinned nightly toolchain

[google-pr-creation-bot]

Automated changes by create-pull-request GitHub action

[gemini-code-assist]

Summary of Changes

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This pull request performs a routine update of the nightly Rust toolchain version specified for continuous integration builds. This ensures that the project's CI processes are running against a more current nightly compiler, which helps maintain compatibility with the latest Rust developments and can proactively identify any potential issues with newer toolchain versions.

Highlights

• CI Configuration Update: The pinned nightly Rust toolchain version used in the project's continuous integration (CI) setup has been updated from nightly-2025-10-17 to nightly-2025-10-23.

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[gemini-code-assist]

Code Review

The pull request updates the pinned nightly toolchain version in the Cargo.toml file. I have identified one issue related to the date format used for the nightly version.

[gemini-code-assist]

The date format for the pinned-nightly version is nightly-2025-10-23. While this is functional, consider using a more standard and easily parsable date format like nightly-20251023 to avoid potential ambiguity or parsing issues in the future. This is a high severity issue because incorrect date parsing could lead to the wrong toolchain being selected, which could cause build failures or unexpected behavior.

I suggest changing the format to nightly-YYYYMMDD.

Suggested change

	pinned-nightly = "nightly-2025-10-23"
	pinned-nightly = "nightly-20251023"