Bump libc from 0.2.105 to 0.2.106 (#4194)

Bumps [libc](https://github.com/rust-lang/libc) from 0.2.105 to 0.2.106.
- [Release notes](https://github.com/rust-lang/libc/releases)
- [Commits](https://github.com/rust-lang/libc/compare/0.2.105...0.2.106)

---
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>
18 jobs for master in 41 minutes and 16 seconds (queued for 5 seconds)
Name Stage Failure
failed
publish-rustdoc Publish
$ git config remote.origin.url "https://${GITHUB_TOKEN}@github.com/paritytech/polkadot.git"
$ git config remote.origin.fetch "+refs/heads/*:refs/remotes/origin/*"
$ git fetch origin gh-pages
fatal: expected flush after ref listing
Running after_script
Running after script...
$ rm -rf .git/ ./*
Cleaning up file based variables
ERROR: Job failed: command terminated with exit code 1