chore: bump signal-hook-tokio from 0.3.1 to 0.4.0

[dependabot]

Bumps signal-hook-tokio from 0.3.1 to 0.4.0.

Changelog

Sourced from signal-hook-tokio's changelog.

signal-hook-tokio-0.4.0

signal-hook-async-std-0.4.0

• Release to bump dependency on signal-hook.

0.4.1

• Don't pin specific dependency versions accidentally.

0.4.0

• Changed the low_level::pipe to look OwnedFd instead of IntoRawFd, to enforce ownership of the file descriptor (#196).

signal-hook-registry-1.4.8

• Restore errno on signal handler exit (#194, #191).

signal-hook-registry-1.4.7

• Using earlier monopolization to reduce binary size (#190).

signal-hook-mio-0.2.5

• Allow mio 1.1

signal-hook-registry-1.4.6

• Reword/improve the safety requirements docs for register (#178).

signal-hook-1.3.18

• Release the special-case removal of AIX for top-level signal-hook too (#169, #176).

signal-hook-async-std-0.3.0

• Bump async-std to 0.2 (#172).

signal-hook-registry-1.4.5

• Fix windows build (#174).

signal-hook-registry-1.4.4

• Get rid of a warning.

signal-hook-registry-1.4.3

• Remove special-case for AIX (#169).

... (truncated)

Commits

• 6e44722 Version bump to 0.4.0
• 80cc0cf Update dependencies
• 2f67df6 Fix some links & link tests
• bbcecf8 Adjust tests for higher minimal rust version
• 09d1e08 I/O safety
• 115d998 Simplify tests
• 4d5fd6a Version registry 1.4.8
• e04514e Merge pull request #194 from hanna-kruppe/save-restore-errno
• 2f3c6e4 save and restore errno
• 017e9b5 Merge pull request #192 from hanna-kruppe/dumb-down-data-structures
• Additional commits viewable in compare view

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