Update Rust crate proc-macro2 to v1.0.87

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
proc-macro2	dependencies	patch	1.0.86 -> 1.0.87

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Release Notes

dtolnay/proc-macro2 (proc-macro2)

### [`v1.0.87`](https://redirect.github.com/dtolnay/proc-macro2/releases/tag/1.0.87) [Compare Source](https://redirect.github.com/dtolnay/proc-macro2/compare/1.0.86...1.0.87) - Check valid punctuation character in `Punct::new` ([#​470](https://redirect.github.com/dtolnay/proc-macro2/issues/470))

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