agent: remove crate signal-hook which are no longer used

Had replaced by tokio::signal.

Signed-off-by: Tim Zhang <tim@hyper.sh>

src/agent/Cargo.lock

@@ -579,7 +579,6 @@ dependencies = [
  "scan_fmt",
  "scopeguard",
  "serde_json",
- "signal-hook",
  "slog",
  "slog-scope",
  "slog-stdlog",
@@ -1511,16 +1510,6 @@ dependencies = [
  "syn 1.0.55",
 ]
 
-[[package]]
-name = "signal-hook"
-version = "0.1.16"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "604508c1418b99dfe1925ca9224829bb2a8a9a04dda655cc01fcad46f4ab05ed"
-dependencies = [
- "libc",
- "signal-hook-registry",
-]
-
 [[package]]
 name = "signal-hook-registry"
 version = "1.2.2"

src/agent/Cargo.toml

@@ -16,7 +16,6 @@ libc = "0.2.58"
 nix = "0.17.0"
 prctl = "1.0.0"
 serde_json = "1.0.39"
-signal-hook = "0.1.9"
 scan_fmt = "0.2.3"
 scopeguard = "1.0.0"
 regex = "1"

src/agent/src/main.rs

@@ -17,7 +17,6 @@ extern crate protocols;
 extern crate regex;
 extern crate scan_fmt;
 extern crate serde_json;
-extern crate signal_hook;
 
 #[macro_use]
 extern crate scopeguard;