Update Rust crate tokio to 1.20

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
tokio (source)	dev-dependencies	minor	1.19 -> 1.20
tokio (source)	dependencies	minor	1.19 -> 1.20

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Release Notes

tokio-rs/tokio

v1.20.0

Compare Source

1.20.0 (July 12, 2022)

Added

• tokio: add track_caller to public APIs (#​4772, #​4791, #​4793, #​4806, #​4808)
• sync: Add has_changed method to watch::Ref (#​4758)

Changed

• time: remove src/time/driver/wheel/stack.rs (#​4766)
• rt: clean up arguments passed to basic scheduler (#​4767)
• net: be more specific about winapi features (#​4764)
• tokio: use const initialized thread locals where possible (#​4677)
• task: various small improvements to LocalKey (#​4795)

Fixed

Documented

• fs: warn about performance pitfall (#​4762)
• chore: fix spelling (#​4769)
• sync: document spurious failures in oneshot (#​4777)
• sync: add warning for watch in non-Send futures (#​4741)
• chore: fix typo (#​4798)

Unstable

• joinset: rename join_one to join_next (#​4755)
• rt: unhandled panic config for current thread rt (#​4770)

v1.19.2

Compare Source

v1.19.1

Compare Source

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