[CrOS Cellular] Modifying the hermes network operation timeout

Our operation timeout was set to 4 min and that is in line with
platform's timeout for carrier call. However, theoretically, the call
could take little over 4 mins end to end if the carrier call itself
takes up 4 mins. We have received some reports of DBUS_NOREPLY that
would confirm this.

Bug: b/244447732
Change-Id: Ia8a14f10a2935840fb5c3593e6e0bd785b8bb10f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4763105
Reviewed-by: Jason Zhang <jiajunz@google.com>
Commit-Queue: Nikhil Nayunigari <nikhilcn@google.com>
Cr-Commit-Position: refs/heads/main@{#1181205}

chromeos/ash/components/dbus/hermes/constants.cc

@@ -6,8 +6,8 @@
 
 namespace ash::hermes_constants {
 
-// 4min * 60s/min * 1000ms/s.
-int kHermesNetworkOperationTimeoutMs = 4 * 60 * 1000;
+// 6min * 60s/min * 1000ms/s.
+int kHermesNetworkOperationTimeoutMs = 6 * 60 * 1000;
 
 // 2min * 60s/min * 1000ms/s
 int kHermesOperationTimeoutMs = 2 * 60 * 1000;