Open Group Policy Editor (gpedit.msc), then select "Computer Configuration"
Right click "Administrative Templates" and select "Add/Remove Templates..."
Click on "Add..." then browse to the location of the "chrome.adm" file and open it

Now go to "Google > Google Chrome" and double click the "Suppress the unsupported OS warning" setting
Select "Enabled", then press "Apply" and "OK",then close the Group Policy Editor
Next time you start Google Chrome you shouldn't see the warning anymore