feat(*): remove the network ns in the shim start

this commit removes the unnecessary nerwork namepsace setup in the
shim start function because it is already been set in youki

Signed-off-by: jiaxiao zhou <jiazho@microsoft.com>

crates/containerd-shim-wasm/src/sandbox/shim/cli.rs

@@ -12,7 +12,6 @@ use shim::Flags;
 use crate::sandbox::instance::Instance;
 use crate::sandbox::shim::events::{RemoteEventSender, ToTimestamp};
 use crate::sandbox::shim::local::Local;
-use crate::sys::networking::setup_namespaces;
 
 /// Cli implements the containerd-shim cli interface using `Local<T>` as the task service.
 pub struct Cli<T: Instance + Sync + Send> {
@@ -53,9 +52,6 @@ where
             .and_then(|a| a.get("io.kubernetes.cri.sandbox-id"))
             .unwrap_or(&id);
 
-        setup_namespaces(&spec)
-            .map_err(|e| shim::Error::Other(format!("failed to setup namespaces: {}", e)))?;
-
         let (_child, address) = shim::spawn(opts, grouping, vec![])?;
 
         write_address(&address)?;