build: Bump once_cell from 1.19.0 to 1.20.2

Bumps [once_cell](https://github.com/matklad/once_cell) from 1.19.0 to 1.20.2.
- [Changelog](https://github.com/matklad/once_cell/blob/master/CHANGELOG.md)
- [Commits](https://github.com/matklad/once_cell/compare/v1.19.0...v1.20.2)

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

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

vmm/Cargo.toml

@@ -56,7 +56,7 @@ mshv-bindings = { workspace = true, features = [
   "with-serde",
 ], optional = true }
 net_util = { path = "../net_util" }
-once_cell = "1.19.0"
+once_cell = "1.20.2"
 option_parser = { path = "../option_parser" }
 pci = { path = "../pci" }
 range_map_vec = { version = "0.2.0", optional = true }