Remove --offline from publish.rs (#12189)

This was added in #12164 but I don't believe that it's necessary for
that operation. That may change the lock file if the crates weren't
previously vendored, so this enables using the network to fetch
dependencies in the lock file that aren't present locally.

Author: alexcrichton

scripts/publish.rs

@@ -176,7 +176,7 @@ fn main() {
             // update C API version in wasmtime.h
             update_capi_version();
             // update the lock file
-            run_cmd(Command::new("cargo").arg("fetch").arg("--offline"));
+            run_cmd(Command::new("cargo").arg("fetch"));
         }
 
         "publish" => {