fix sha

Signed-off-by: emdneto <[email protected]>

Author: emdneto

.github/workflows/misc_0.yml

@@ -10,7 +10,7 @@ on:
   pull_request:
 
 env:
-  CORE_REPO_SHA: opentelemetrybot/prepare-release-1.28.2-0.49b2
+  CORE_REPO_SHA: release/v1.28.x-0.49bx
   CONTRIB_REPO_SHA: main
   PIP_EXISTS_ACTION: w