Update README.md

Changed "Edge Site" to "Edge Cloud Zone"

Author: Kevsy

code/API_definitions/README.md

@@ -1,7 +1,7 @@
 The Edge Cloud suite of APIs is split into 4 categories, based on the intents listed [here](https://github.com/camaraproject/EdgeCloud/blob/main/documentation/SupportingDocuments/Harmonisation%20of%20APIs/describing%20and%20harmonising%20the%20Edge%20APIs.md).
 
 # Discovery
-Discover the Edge site with the shortest network path to an end user terminal,find out which is the optimal Edge site for your specifc application, register your Edge-hosted application endpoints for rapid connectivity to the optimal Edge site.
+Discover the Edge Cloud Zone with the shortest network path to an end user terminal, find out which is the optimalEdge Cloud Zone for your specifc application, register your Edge-hosted application endpoints for rapid connectivity to the optimal Edge Cloud Zone.
 
 # Workload Orchestration
 Lifecycle management of the Edge resources and servers for your applications
@@ -10,4 +10,4 @@ Lifecycle management of the Edge resources and servers for your applications
 Management (CRUD) of the edge resources by the application providers for the consumption by edge applications.
 
 # Traffic Influence
-Influence traffic routing to ensure optimal network perfromance based on user mobility, application demand, best edge site. 
+Influence traffic routing to ensure optimal network perfromance based on user mobility, application demand, best Edge Cloud Zone.