Update comment.yml (Azure#21208)

Author: ruowan

.github/comment.yml

@@ -21,6 +21,10 @@
     label: SuppressionReviewRequired
     onLabeledComments: "Hi @${PRAuthor}, one or multiple validation error/warning suppression(s) is detected in your PR. Please follow the [Swagger-Suppression-Process](https://dev.azure.com/azure-sdk/internal/_wiki/wikis/internal.wiki/85/Swagger-Suppression-Process) to get approval."
 
+- rule:
+    type: label
+    label: CI-MissingBaseCommit
+    onlabeledComments: "Hi, @${PRAuthor}, For review efficiency consideration, when creating a new api version, it is required to place API specs of the base version in the first commit, and push new version updates into successive commits. You can use OpenAPIHub to initialize the PR for adding a new version. For more details refer to the [wiki](https://dev.azure.com/azure-sdk/internal/_wiki/wikis/internal.wiki/208/OpenAPI-Hub-Adding-new-API-version). Or you could onboard [API spec pipeline](https://dev.azure.com/azure-sdk/internal/_wiki/wikis/internal.wiki/606/Enable-API-Spec-Pipeline)"
 - rule:
     type: label
     repoAllowList: