Update New-CsTeamsEmergencyCallingPolicy.md

Removed the line that says "this parameter is not supported" for ExternalLookupMode

Author: devikabhagwats

skype/skype-ps/skype/New-CsTeamsEmergencyCallingPolicy.md

@@ -69,7 +69,7 @@ Accept wildcard characters: False
 ```
 
 ### -ExternalLocationLookupMode
- Enable ExternalLocationLookupMode. This parameter is currently not supported.
+ Enable ExternalLocationLookupMode. 
 
 ```yaml
 Type: ExternalLocationLookupMode