build(deps): bump once_cell from 1.7.0 to 1.7.2

Bumps [once_cell](https://github.com/matklad/once_cell) from 1.7.0 to 1.7.2.
- [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/v1.7.0...v1.7.2)

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

Cargo.lock

@@ -1029,9 +1029,9 @@ dependencies = [
 
 [[package]]
 name = "once_cell"
-version = "1.7.0"
+version = "1.7.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "10acf907b94fc1b1a152d08ef97e7759650268cf986bf127f387e602b02c7e5a"
+checksum = "af8b08b04175473088b46763e51ee54da5f9a164bc162f615b91bc179dbf15a3"
 
 [[package]]
 name = "opaque-debug"