cargo: bump once_cell from 1.10.0 to 1.12.0

Bumps [once_cell](https://github.com/matklad/once_cell) from 1.10.0 to 1.12.0.
- [Release notes](https://github.com/matklad/once_cell/releases)
- [Changelog](https://github.com/matklad/once_cell/blob/master/CHANGELOG.md)
- [Commits](https://github.com/matklad/once_cell/compare/v1.10.0...v1.12.0)

---
updated-dependencies:
- dependency-name: once_cell
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

Cargo.lock

@@ -2436,9 +2436,9 @@ dependencies = [
 
 [[package]]
 name = "once_cell"
-version = "1.10.0"
+version = "1.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "87f3e037eac156d1775da914196f0f37741a274155e34a0b7e427c35d2a2ecb9"
+checksum = "7709cef83f0c1f58f666e746a08b21e0085f7440fa6a29cc194d68aac97a4225"
 
 [[package]]
 name = "oorandom"

Cargo.toml

@@ -46,7 +46,7 @@ native-tls = "0.2"
 num_cpus = "1.13"
 num-derive = "0.3"
 num-traits = "0.2"
-once_cell = "1.10.0"
+once_cell = "1.12.0"
 percent-encoding = "2.0"
 pgp = { version = "0.7", default-features = false }
 pretty_env_logger = { version = "0.4", optional = true }