Update hostname from 0.3.1 to 0.4.1

Summary:
Update the third-party hostname crate from 0.3.1 to 0.4.1. Required by below-model.

Release notes:

- https://github.com/djc/hostname/releases/tag/v0.4.0
- https://github.com/djc/hostname/releases/tag/v0.4.1

Reviewed By: kev-common, michel-slm

Differential Revision: D97519077

fbshipit-source-id: cae79974f34dada7b1b13a481482e1b9c19606b6

Author: David Tolnay

below/model/Cargo.toml

@@ -19,7 +19,7 @@ common = { package = "below-common", version = "0.11.0", path = "../common" }
 enum-iterator = "2.3.0"
 ethtool = { package = "below-ethtool", version = "0.11.0", path = "../ethtool" }
 gpu_stats = { package = "below-gpu-stats", version = "0.11.0", path = "../gpu_stats" }
-hostname = "0.3"
+hostname = "0.4"
 os_info = "3.14.0"
 procfs = { package = "fb_procfs", version = "0.11.0", path = "../procfs" }
 regex = "1.12.3"