Process: Preserve environment when "runAsRoot" is enabled

Change-Id: I2078925b48d8fc3053e2be9632248e3fff9ea608
Reviewed-by: hjk <hjk@qt.io>

src/libs/utils/process.cpp

@@ -226,6 +226,7 @@ void DefaultImpl::start()
 
     if (m_setup.m_runAsRoot && !HostOsInfo::isWindowsHost()) {
         arguments.prepend(program);
+        arguments.prepend("-E");
         arguments.prepend("-A");
         program = "sudo";
     }