Update for KeyVault CODEOWNERS (#42285)

This adds the `azure-sdk-write-keyvault` team as code owners, removing `lgonsoulin`.

Author: adarce

.github/CODEOWNERS

@@ -157,12 +157,12 @@
 # PRLabel: %Cognitive - Health Insights
 /sdk/healthinsights/                                                 @tomsft @koen-mertens
 
-# AzureSdkOwners: @mccoyp
+# AzureSdkOwners: @mccoyp @Azure/azure-sdk-write-keyvault
 # ServiceLabel: %KeyVault
-# ServiceOwners:                                                     @cheathamb36 @chen-karen @lgonsoulin
+# ServiceOwners:                                                     @cheathamb36 @chen-karen @Azure/azure-sdk-write-keyvault
 
 # PRLabel: %KeyVault
-/sdk/keyvault/                                                       @mccoyp
+/sdk/keyvault/                                                       @mccoyp @Azure/azure-sdk-write-keyvault
 
 # PRLabel: %Load Test Service
 /sdk/loadtesting/azure-developer-loadtesting/                        @prativen @mitsha-microsoft @ninallam