test breaking change mlc in js (#3451)

* `

* `

* Revert "`"

This reverts commit c26fc6a.

specificationRepositoryConfiguration.json

@@ -14,7 +14,8 @@
     },
     "azure-sdk-for-js": {
       "integrationRepository": "azure-sdk/azure-sdk-for-js",
-      "mainRepository": "Azure/azure-sdk-for-js"
+      "mainRepository": "test-repo-billy/azure-sdk-for-js",
+      "mainBranch": "test_repo_breaking_change_mlc"
     },
     "azure-sdk-for-net": {
       "integrationRepository": "azure-sdk/azure-sdk-for-net",
@@ -82,4 +83,4 @@
     "@azure-tools/typespec-ts": "azure-sdk-for-js",
     "@azure-tools/typespec-go": "azure-sdk-for-go"
   }
-}
+}