Update New-ComplianceSecurityFilter.md

Just changed the example 3 where we use mailbox_countrycode as US when in fact we should use the numeric value, in this case US is 840.
https://www.iso.org/obp/ui/#iso:code:3166:US

Author: rtmorato

exchange/exchange-ps/exchange/New-ComplianceSecurityFilter.md

@@ -53,7 +53,7 @@ This example allows the users donh and suzanf to search only the mailboxes that
 
 ### Example 3
 ```powershell
-New-ComplianceSecurityFilter -FilterName USDiscoveryManagers -Users "US Discovery Managers" -Filters "Mailbox_CountryCode -eq 'US'" -Action All
+New-ComplianceSecurityFilter -FilterName USDiscoveryManagers -Users "US Discovery Managers" -Filters "Mailbox_CountryCode -eq '840'" -Action All
 ```
 
 This example allows members of the US Discovery Managers role group to perform all compliance search actions only on mailboxes in the United States.