Update build json files for 2.12.1 hotfix release (#12785)

* update jsons

* Revert "update jsons"

This reverts commit a0af58e.

* Update build.json

Author: zeusongit

tools/autobuild/build.json

@@ -2,8 +2,8 @@
   "product_id": "DYN",
   "release_id": "2.12.0",
   "master_id": "Win64",
-  "build_id": "2.12.0",
-  "name": "2.12.0",
-  "build_milestone": "FCS",
+  "build_id": "2.12.1",
+  "name": "2.12.1",
+  "build_milestone": "Update 1",
   "description":"Build"
 }