Create new Process object only once in Resource Monitoring Windows

[evgenyfedorov2]

GetCurrentProcessMemoryUsage method creates a new Process object on every method call:

public ulong GetCurrentProcessMemoryUsage()
{
    using Process process = Process.GetCurrentProcess();
    return (ulong)process.WorkingSet64;
}

Instead, it could have created it once and then reusing it for the application lifetime. This should improve performance.

[haipz]

This might hit performance issue:

[makazeu]

Not sure why GetCurrentProcess is really cpu-heavy

[evgenyfedorov2]

Fixed in #5597