kata-sys-util: Fix rust compile errors

- Bump version of rand to avoid error
- Fix based on
 https://github.com/kata-containers/kata-containers/pull/7033
 , but not directly cherry-picked due to vendor
 conflicts

Fixes: #7032
Signed-off-by: stevenhorsman <steven@uk.ibm.com>

src/runtime-rs/Cargo.lock

@@ -1460,7 +1460,7 @@ dependencies = [
  "nix 0.24.3",
  "oci",
  "once_cell",
- "rand 0.7.3",
+ "rand 0.8.5",
  "serde_json",
  "slog",
  "slog-scope",