fix: Update tag handling to include existing tags in resource group

Author: Avijit-Microsoft

infra/main.bicep

@@ -112,11 +112,18 @@ param createdBy string = empty(deployer().userPrincipalName) ? '' : split(deploy
 resource resourceGroupTags 'Microsoft.Resources/tags@2021-04-01' = {
   name: 'default'
   properties: {
-    tags: {
-      ... tags
-      TemplateName: 'KM Generic'
-      CreatedBy: createdBy
-    }
+    tags: union(
+      reference(
+        resourceGroup().id, 
+        '2021-04-01', 
+        'Full'
+      ).tags ?? {},
+      {
+        TemplateName: 'KM Generic'
+        CreatedBy: createdBy
+      },
+      tags
+    )
   }
 }
 

infra/main.json

@@ -5,7 +5,7 @@
     "_generator": {
       "name": "bicep",
       "version": "0.37.4.10188",
-      "templateHash": "10686282742508674905"
+      "templateHash": "4854945365103887323"
     }
   },
   "parameters": {
@@ -187,7 +187,7 @@
       "apiVersion": "2021-04-01",
       "name": "default",
       "properties": {
-        "tags": "[shallowMerge(createArray(parameters('tags'), createObject('TemplateName', 'KM Generic', 'CreatedBy', parameters('createdBy'))))]"
+        "tags": "[union(coalesce(reference(resourceGroup().id, '2021-04-01', 'Full').tags, createObject()), createObject('TemplateName', 'KM Generic', 'CreatedBy', parameters('createdBy')), parameters('tags'))]"
       }
     },
     {