Bump libc from 0.2.107 to 0.2.108 (#4343)

Bumps [libc](https://github.com/rust-lang/libc) from 0.2.107 to 0.2.108.
- [Release notes](https://github.com/rust-lang/libc/releases)
- [Commits](https://github.com/rust-lang/libc/compare/0.2.107...0.2.108)

---
updated-dependencies:
- dependency-name: libc
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
23 jobs for master in 42 minutes and 9 seconds (queued for 2 seconds)
Name Stage Failure
failed
spellcheck Test
[2021-11-22T10:55:30Z INFO  cargo_spellcheck::action] ✅ /builds/parity/polkadot/node/network/collator-protocol/src/error.rs
[2021-11-22T10:55:30Z INFO cargo_spellcheck::action] ✅ /builds/parity/polkadot/node/network/collator-protocol/src/collator_side/tests.rs
[2021-11-22T10:55:30Z INFO cargo_spellcheck::action] ✅ /builds/parity/polkadot/node/network/collator-protocol/src/validator_side/tests.rs

real 1m32.157s
user 5m10.763s
sys 1m23.855s
Cleaning up file based variables
ERROR: Job failed: exit code 1