Update rustls requirement from 0.21.0 to 0.22.1

[dependabot[bot]]

Updates the requirements on rustls to permit the latest version.

Release notes

Sourced from rustls's releases.

0.21.10

TLS 1.2 servers now remove session tickets after observing a failure to decrypt, preventing future resumption with the same unusable ticket.

What's Changed

• remove the TLS 1.2 session ticket on DecryptError by @​Geal in rustls/rustls#1668
• 0.21.10 release preparation by @​cpu in rustls/rustls#1678

Full Changelog: https://github.com/rustls/rustls/compare/v/0.21.9...v/0.21.10

Commits

• cf6aa80 Cargo: version 0.21.9 -> 0.21.10
• 4ee33ae version: allow manual_non_exhaustive
• f628518 remove the TLS 1.2 session ticket on DecryptError
• bbd9abc Cargo: v0.21.8 -> v0.21.9
• 5edc126 Use BorrowedCursor & BorrowedBuf from core::io
• 7abd73f Opt in to feature(core_io_borrowed_buf)
• c34477a Cargo: 0.21.7 -> 0.21.8
• 8cf2594 sign: fix clippy get-first warning
• ecc6cde Flush writers before potentially expecting a response
• 53adb9d docs: adjust ring platform compatibility
• Additional commits viewable in compare view

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[djc]

See #1715.

[dependabot[bot]]

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