Update mde-planning-guide.md

Author: denisebmsft

defender-endpoint/mde-planning-guide.md

@@ -54,7 +54,7 @@ The steps to deploy Defender for Endpoint are:
 
 Here's a list of prerequisites required to deploy Defender for Endpoint:
 
-- You're a Global Administrator
+- You're a Security Administrator
 - Your environment meets the [minimum requirements](minimum-requirements.md)
 - You have a full inventory of your environment. The following table provides a starting point to gather information and ensure that stakeholders understand your environment. The inventory helps identify potential dependencies and/or changes required in technologies or processes.