update with new changes (#25299)

Author: l0lawrence

specification/eventgrid/Azure.Messaging.EventGrid/main.tsp

@@ -4,7 +4,10 @@ import "@typespec/versioning";
 import "@azure-tools/typespec-azure-core";
 
 @useAuth(
-  ApiKeyAuth<ApiKeyLocation.header, "SharedAccessKey"> | OAuth2Auth<[
+  {
+    type: AuthType.http,
+    scheme: "SharedAccessKey",
+  } | OAuth2Auth<[
     {
       type: OAuth2FlowType.implicit,
       authorizationUrl: "https://login.microsoftonline.com/common/oauth2/authorize",

specification/eventgrid/data-plane/Microsoft.EventGrid/preview/2023-06-01-preview/EventGrid.json

@@ -36,7 +36,7 @@
   ],
   "security": [
     {
-      "ApiKeyAuth": []
+      "http": []
     },
     {
       "OAuth2Auth": [
@@ -45,18 +45,16 @@
     }
   ],
   "securityDefinitions": {
-    "ApiKeyAuth": {
-      "type": "apiKey",
-      "name": "SharedAccessKey",
-      "in": "header"
-    },
     "OAuth2Auth": {
       "type": "oauth2",
       "flow": "implicit",
       "authorizationUrl": "https://login.microsoftonline.com/common/oauth2/authorize",
       "scopes": {
         "https://eventgrid.azure.net/.default": ""
       }
+    },
+    "http": {
+      "type": "basic"
     }
   },
   "tags": [],