Apply suggestion from @v-ccolin

Author: v-ccolin

articles/firewall/roles-permissions.md

@@ -31,7 +31,7 @@ To add any missing permissions listed here, see [Update a custom role](../role-b
 
 ## Permissions
 
-Depending on whether you're creating new resources or using existing ones, add the appropriate permissions from the following list for Azure Firewall in a hub VNET:
+Depending on whether you're creating new resources or using existing ones, add the appropriate permissions from the following list for Azure Firewall in a hub virtual network:
 
 | Resource | Resource status | Required Azure permissions |
 |---|---|---|